Buzz, Wave, and Gmail Chat (including Video) aren't enough for you? How about Gmail Labs, which didn't exist 2 years ago, but now lets you skin Gmail, use keyboard shortcuts, embed youtube videos, etc. etc.? Calendar integration, a better text editor, embedded photos, multiple simultaneous attachment uploads w/ progress bars, better filters, incrementally better spam protection, plus the fact that I now have 7.5 gigs of space in my inbox, all while fending off attacks from Chinese hackers?

I think you grossly underestimate the amount of things they've accomplished in the past year, and the number of people it takes to run a service this popular. Facebook releases with grandiose redesigns, prompting temporary revolts among their users. Gmail improves incrementally, so much so that I can't imagine living without it as my primary e-mail client, but the sense of novelty that comes with a massive redesign is lost. Personally, I prefer Gmail's approach.

Software as popular as Gmail is like an iceberg: most of the engineering effort doesn't go towards user-visible features but towards the -ilities: http://en.wikipedia.org/wiki/Ilities