I dabbled a little in some of the later beta stages. To be clear, I didn't delve into the game very deeply at all, so a lot of these are surface impressions.
To start, the game is very pretty. And while my computer is not off-the-shelf, it is starting to noticeably lag behind in the hardware department. Yet, I had no trouble rendering anything the game threw at me, though I didn't run it extensively at Ultra settings.
It is also, in some ways, very much a "WoW Clone." To be clear, I don't mean this in a bad way, since I love WoW, but a quick perusal of some of the talent trees--sorry, soul trees--show a number of abilities that seem to be lifted directly out of the WoW talent trees, some nearly word-for-word. Class mechanics are much of the same too--the rogue-like class operates under a 5-point combo point system with finishers, all of which seemed to be pretty much old hat. Similarly, the warrior class operates with a three-point attack point system that stacks on the character from certain attacks, which is pretty much exactly what WoW Paladin's Holy Power system is--hell, one of the specializations main attacks is even a shield slam that buffs your block skill, exactly like a protection paladin.
But, despite this, Rift does take things in different directions. The inclusion of buff-and-debuff specializations like the bard adds an extra level of complexity that WoW is missing, and the combinations of specs look like you could do some really interesting things. So, while Rift does grow out of WoW in a lot of ways, I feel like it's less copying WoW and more using it as a foundation and expanding upon it. Which is a great way to build a player base, really. Having played WoW for years, each of the classes I tried in Rift were extremely easy to pick up and play, and the talent trees and abilities were very easy to understand and to navigate.
I'm kind of torn, really. It seems lijke a great game--very, very polished for a pre-release MMO--and even better one that would be extremely easy to transition into. On the other hand, I'm not really sold on the game having enough interesting content at endgame to convince me it's worth giving up a max-level character and a great guild in WoW to play it. Try it, sure, but the endgame is going to have to really, really impress me to make the change worth the effort. Like I said, I didn't get very deep into the game (starting areas, at best) but I think they're going to have to up their game a bit and show me that they can really make their own changes to the WoW system work.