I doubt that Ubuntu can move fast enough to capture tablets; as far as Linux winning the tablet wars, I definitely think that will happen but it will be Android that wins, not Ubuntu. Google has put years and years of effort into tuning the kernel for power savings, eliminating unnecessary things and adding new code. Ubuntu's kernel would need significant modifications to be competitive in the mobile market. I'm sure they'll follow and build a tablet Ubuntu, but I seriously doubt it'll be competitive in the market. iOS and Android are years and years ahead in that regard.