A year ago, I wasn't sure how much longer my ancient (but still functioning!) 2008 MBP would be going on. So I went shopping. Found the same tradeoffs Marco mentions here: I didn't like the sealed nature of the newer offerings (and also, AFAICT no screen density can make up for the inexplicably missing matte displays).
I ended up buying a used 2.6Ghz i7 8GB 15" matte MBP instead of anything new from Apple, though.
About the only complaint I have is that Mavericks seems neither as stable or as well-performing as Snow Leopard, which seems to be the last time Apple released an OS that was a strict improvement over previous releases. Too bad it's no longer safe to run given the state of updates.
It actually runs faster now than it did with the stock HD and Mountain Lion! Granted, I'm not doing a lot of heavy computing with it. For web surfing and the basics it still works great.