1.10 Beta
I've tried it, with several different "legit" (I built em with 1.09 Character Editors and imported em to 1.10) character builds, and I have to say that the currently popular 1.09 builds are going to have a tough time in 1.10's hell difficulty.
Many of the most popular skills have been heavily nerfed, such as Frozen Orb, Guide, Multi-Shot, etc. These skills have either gotten their damages SLASHED or something to that effect, making them difficult to use.
However, many of the skills that many people have disregarded to this point have been boosted through the addition of synergies, which raise their damage to the point that they become very viable tools at later points in the game.
Finally, the new Unique Items and 1.10 Runewords are EXTREMELY powerful. If you visit the Arreat summit and check them out, you'll be pleasantly surprised.
I think the new patch will ultimately be found to be well balanced, but geared more towards people who actually want to "play" the game, as opposed to the vast majority that play now who want to collect, trade, and sell "godly" gear and PK and duel and cow and rush and whatnot (I have to admit, I DO belong to this class
)
Anyway, that's just a quick run through of what I've seen in my limited experience with the Beta Release. Feel free to PM me for more details, I'll be happy to help you out.
Just my .02
-Zak