I am installing it on my MBP right now. Going to run it on there, make sure everything works good then install it on my MP.
So far it looks amazing. The under the hood changes are REALLY impressive. This is a really strong re-tooling of the OS. Andy Inahtko said it's very fast, so fast it's cutting in on his \"reach for a Dr. Pepper while I wait for my programs to open\" time.
It doesn't have anti-virus software, it does have built in mal-ware protection:
http://www.macworld.com/article/142457/2009/08/snowleopard_malware.html VERY nice.