Finally got in a game of 8th Edition on Saturday. I went down to Legends in Cupertino to play with the store owner. Turned out that he didn't have time to play himself. However, he was trying to get one of his employees up to speed on the rules so they could start running events in the store, so I ended up playing a teaching game. *shrug* It's better than nothing. Plus, I had to make sure I understood the rules well enough to explain them to someone who was mainly familiar with the 40k rules but knew a pretty decent amount about the Fantasy fluff.
It's hard to draw any conclusions from that game. He was playing an Orc army that didn't belong to him and looked like it was a couple of editions old. We put together the best 15oo point list we could from the models we had available, and I tried to dissuade him from some non-optimal choices he was making based on his 40k experience (no, you really should make one big unit of Black Orks, and you should probably put your General in there instead of two small units and 5 guys to hang out with your General). But he had fun and we got through the game without any major issues.
I already like the Magic system better than the previous edition. Magic defense no longer has to be a list design requirement. I tried out a Level 2 Sorceress with the Tome of Furion (knows one additional spell) and was quite happy with the result. Taking the Tome always seemed like a waste to me in the previous edition since you rarely had enough power dice to successfully cast the couple of spells you already knew. But with the new rules for generating power dice, a single lower level caster can have significantly more dice to work with than before (7 on average, up from 4). Suddenly 15 points to know an additional spell seems like a pretty good use of points. Previously if you wanted to be more effective you had to spend significantly more points and another Hero slot to get another caster, just so you could get a couple more power dice to work with. Now, adding another caster just splits the randomly generated power dice between them and all you really gain is a couple more spells and maybe some additional magic items. Granted, those can be valuable in and of themselves if you are going for a heavy magic list. But now instead of needing a 'scroll caddy' you can turn that same amount of points into a decent amount of offensive magic. I had been playing a magic heavy list with 3 casters until 8th came out. It seems like adding more casters in 8th will result in diminishing returns. You might gain flexibility by adding additional Lores, and maybe some extra punch with additional magic items, but I don't see the power scaling up the way it did in the last edition. I think this it a good thing.