Well I love share sheets, iCloud syncing, and AirPlay, personally. Gatekeeper is a great compromise between a fully locked down system and a fully vulnerable one. And the new Safari is the best Safari ever, as the saying goes. So I count 4.5 on my end.
Anyway, an OS is more than the sum of its newest features. On the whole, OS X 10.8 is a stable, polished, powerful, fully-featured operating system. There might not have been a big feature like Time Machine or Exposé in a couple versions, but I'd much rather use 10.8 than 10.5.
Gatekeeper is an okay compromise. I'd feel better about it if they didn't include restrictive app policies. What if I want to run apps that are signed by a certificate from some third party CA? I'd feel great about it if it would also inform me what permissions are being granted and let me disable arbitrary permissions like internet access.
I think 10.7 and 10.8 bring more irritations than anything else. iCloud sync and Gatekeeper are the only things I think are worth upgrading for, but the Gatekeeper implementation is still lacking and unfree, and I use other services to sync my files (I also think the implementation of iCloud leaves something to be desired... and it's another form of lock-in). I'm still using 10.6 and shall use it for the foreseeable future; at least until my next computer, which will most likely be running Linux.
Go look at that page real quick and count the number of things that are good. Not "not bad" or "you can turn it off". Good.