The first build was buggy (as usual), the only problems I've hit so far is the lack of support for my current build of proxifier- but theyre sending an updated version for lion and i have quickbooks 2010, which doesnt work 100% (addons such as email forms, etc... functionally, it still works for the basics like checks, registers, invoices, estimates, customers, etc) in lion and qb support advises they'll never patch it, upgrade... Sucks, but QB 2012 is in the mail.
Other than that, love it. Glad I made the switch, and even happier that I wanted until 10.7.2.