Hey guys, I have the early 2011 13". I upgraded to 8GB of RAM and a 500GB HDD. (I actually went SSD, but the thing broke (crucial M4) in less than 2 weeks so I returned it) Anyways, I'm super happy this Mac. It's my first jump to Mac from a Windows PC. I find it way more stable than windows. I have only 2 issues really. 1 is that sometimes my page out becomes high, like a few Gigs. i *think* this only happens when i download for a long time, not sure. With what i do on there, and the amount of RAM i have, it doesn't make sense that it should page out that much. I beach ball occasionally. The other issue is more annoying. If I have been using the computer for awhile, and then I watch an HD Movie (MKV or otherwise) sometimes the display gets all blocky and messed up for a few seconds. However if I restart the computer, and then watch the HD Movie, this generally doesn't happen. At either time I don't run other programs while watching the movie. So, other than these two issues, I'm happy with Lion and reluctant to upgrade to Mountain Lion. I don't care about iMessage on the mac, or any other new mountain lion features. I'm thinking the upgrade might be more trouble then it's worth. Any thoughts? As for those 2 issues, perhaps the page outs will be fixed by ML? But I have my doubts that the HD Video issues will be fixed. Anyone have any thoughts on these issues? Maybe how to fix them if they are fixable. Thing is, one of the things I do the most on the mac is watch HD videos, so this problem is pretty annoying. I should also mention I have the MBP hooked up to my 40" HDTV when I watch movies.