It will be interesting to see what happens with the Motorola acquisition.
Right now, Samsung is Android to a large degree. They're the only Android phone vendor that's actually making money, and they're selling a ton of units compared to the other vendors.
I'm amazed RIM has lasted this long. From what I've read I'm pleasantly surprised. I know there is still a small minority that refuses to own a phone without a physical keyboard, and the few I know aren't very happy with the few Android phones they've tried with keyboards. They may be able to get enough of a niche there to hold on and survive a bit.