I have a MacBookPro 3,1 (2007) model with Lion and it runs ok. I do think its a little faster booting up now -
As to the the future of OS X, I agree that we're going to see further consolidation between iOS and OS X - what really worries me is if that if Apple start to prohibit installation of applications downloaded through the web, well that will be it for me. While there are some advantages to Apples curated App Store (no malware), I don't want to lose the freedom of downloading and installing apps off the web.
