I still think buying Opera, and adopting/adapting would be a good thing for Microsoft. It would give them a major playing hand in the mobile browser market too. From Opera's perspective, they might gain a lot of users overnight, which may or may not be a good thing. But i do think Opera as a browser is the neatest, most feature-rich and yet unbloated piece of software i've seen. And they deserve a bigger desktop mark…
I like my Opera as it is thanks.
Buy stake in Opera, maybe adopt it as a default browser, but i would definitely leave the dev process alone. But judging from how large companies act, dreaming this is just silly on my part.