Safe to say that it is very opinionated, so to add some further wood to the fire, here is my take on some of the units...
I'll start with what I think are the winners.
High Elves Core: Simply because the book now offers more options in core than previous, this is an improvement. Its not based on points cost or anything of the like, the simple truth is a High Elves player can now bring to the party several new combinations and themes based purely of Reavers and Silverhelms making core.
Dragon Princes: A small price drop combined with gaining Ithilmar barding gives High Elves a 9" base move heavy cav! Fastest in the game. Combine that with the 2 attacks they have, huge banner allowance, magic weapon for the champion and throw in the 6+ ward to synergise with magic lore, this unit gains a lot. They still retain re-rolls to hit helping avoid the rubber lance syndrome, the only let down being st3. But then again they are not a unit designed for protracted combats. Hammer unit if I ever seen one.
Archers: With martial prowess allowing three ranks of shooting and them getting a discount for their long bows these guys are the clear winner. The fact they can fight just as well as spearmen is defining. They are winners because they get a 1 point discount compared to all the other core options. Elves are 6 (approx) points in this book, and longbows are 3 points, yet these guys come in at 10! BS4 st3 30" range shooting for 10 points is ok. 9 points Yes please!
Archmages: Special mention here. A decent price drop, +1 to cast high magic, ability to choose between 9 different lores and some rather good arcane items (here's looking at you 1+ book of Hoeth) make these guys great value.
Characters: In general huge boost here. From price drops to mount options, everything got better. And we can't not mention the new character options which will bring some interesting builds/options to the table. A clear winner overall for the book here.
Spearmen: Still over costed but only by a fraction. This is mainly because, although they are ASF WS4 etc they still only bring St3 t3 to the table. 5+ save dosn't cut it when you are investing 9 points a model. They are however the only core unit that can have a magical banner. Basically I think the base cost of an Elf should have been 5 points, or the spears should be free. Currently (based on spearmen) an elf costs roughly 6 points assuming light armour is worth 1.
Seaguard: Still stuck in between trying to be useful and trying to do to much. These guys are over costed by 1-2 points IMO. At 12 points (with shields) they work out to be 10 points without the bow (as bows are worth 2). We can already buy 9 point spearmen which leads me to... If the basic Elf has a cost of 6 points, add 2 for the bow, 1 for light armour, 1 for shield and 1 for spear we get 11. So why the extra point over and above other normal Elfs GW???
Swordmasters of Hoeth; Another design failure here IMO. GW gave them light sabres but stopped short of allowing them to use them in combat. They suffered the loss of re-rolls to hit but droppedin points to compensate. They also don't get much advantage out of Martial Prowess since you only get 1 supporting attack. These guys would have been made better if they got a -1 to hit, or a 4+ parry save in combat to represent their unequalled abilities. Alas they loose more than they gain.
The Middle Ground
Dragons: Whilst not being a loser in this book they are not a clear winner either. Dragons still bring a lot of 'punch' to any High Elves list however to achieve that punch you need to go the full monty and get a star dragon, so you can kiss good bye 600 odd points. The sun dragon just dosn't stack up against the new value of 150 points a griffon, let alone the closely priced Phoenix options (although they cannot be mounted by 'normal' characters). Moon dragons don't offer much more than what a Phoenix can offer for a lot more. Typical of new books the old dragon kit is not the new phoenix kit. This is rules driving sales!
White Lion Chariots: They are good, but not great, and will probably be left on the shelf in the most part. They have marginally greater damage output than a WoC Chariot but nowhere near the survivability as them for similar points, but tote stubborn which will be largely useless as they wont survive a combat long enough to make use of the rule. Design failure here. Unit could have done with an extra point of toughness or a price drop of about 20 points.
Phoenix Guard: While not great they are still good. I mean 4+ ward for 15 points. Still good value. Still only T3/St3.
The new stuff
Loremaster of Hoeth: Now this is the star of the new book to me. A great concept and well executed IMO. On face value it looks like they have put a lot of thought into its power level, cutting it back to a level 2, giving access at 8 signature spells, and making him semi viable in combat. What amuses me most is some people are crying fowl and saying this dude is undercosted! If anything this guy is a little to cheap. 8 Spells...8! Some people just have their head in the clouds I think
And that leads me into Lothern Skycutters: Another unique concept from GW. 10 points for effort, however I think they missed the boat a little with this one. Flying chariots (despite what people think of the model, I rather like it) if well executed would have been amazing, but I can't help but think they got this one a little off side. Don't get me wrong, I think it is well priced for what it is capable of doing (as a concept) by the rules let it down a little. Flying is great, but chariots are not able to march, thus it misses a lot potential (look to see if 9th edition changes this). Mounting a bolt thrower on it is also a great concept that falls short on the execution. Strength 5 D3 wounds is fine, but the fact it suffers movement penalties for moving and shooting for a weapon that is designed to move and shoot is poor design. If this had BS5 and/or no move and shoot penalties it would be perfect. If it was able to march it would be amazing, if not a little under costed.
Phoenīcēs: These guys are the stars. Options for unit assist/quazi buff types (frost) and damage/rank and file killing (fire) allow a lot of flexibility in the book. A multitude of special rules I wont dwell here as these guys have been done to death (and rebirth) elsewhere.
Overall the book will be a victim of its own success. The internal balance is so good it has most veteran High Elves players confused as to what is the next 'net list'... There are a lot of hard choices to be made and it will be a while before we see a common list played. The external balancing is a bit off with (my prediction) the power level eventually settling in the upper 1/3 of the books. Don't get me wrong, the book is a good one, but its definitely not the next 'Ogres' or 'WoC', despite the ramblings of Daemon players everywhere. (If Daemon players can't figure out how to beat High Elves with the BotWD, well theres no helping you. Seriously its not that bad!).
The new book definitely is a big boost to the ailing 7th edition volume. High Elf players everywhere should be rejoicing in jubilation as the book moves solidly into mid upper tier. This is backed up by all the 'bandwagoners' that can be seen scrambling to get some new filth on the table. Alas, there are still several mentally retarded people out there that don't think the new book is 'good'. These are the die hard fanboys stuck in a 4th/5th edition mindset. Can't see the forest for the trees. Doomed to fail.
Watch out for some of the WHFB veterans picking up High Elves as these guys, with their fresh eyes will be pushing the book to the limits.
Then there are the powerplays. It seams like only yesterday we got the new WoC filth. Oh wait, it was just yesterday! Are High Elves the new WoC? Hell no. But the book is still damn good.