Huh. This is pretty big news.
It's easy for people to point at recent games and try to make some sorts of conclusions but I think that's being a bit too game-centric with perspective. These guys have been doing this for years and Bioware has become the megalithic conglomerate in the recent ones. They've probably gone as far as they can go and I'm sure the enterprise doesn't feel like it once was - maybe the size is now too much for them to want to cope with on a long-term scale. You can understand that they just wanted something different and that other life issues affected things.
The other question about whether this will have much material aspect on Bioware's games is also hard to answer. There's lots of great people there I reckon and hopefully that will work out, though who knows if the successors will arise from inside Bioware or outside of it.