Quicken's TurboTax is the slickest and deepest online app I've used. I've been a fan since 2003, and they just kept getting better. One thing that stood out this year was the unobtrusive but clear integration of their help forums into every page you're working with. There's a sidebar that has the most popular questions for the current section, ordered by view popularity. It's applying Web 2.0-ish techniques, using page views to rank user-generated content, but for once it's solving a painful problem. Maybe I'm just old, but I feel sad when I see all the great work teams are doing to solve mild consumer itches like photo organization that are already over-served, and my doctor's practice still runs on DOS.
It was fascinating to read John Doerr's thoughts on how Intuit was built, from his introduction to Inside Intuit. I've never managed to computerize my household finances (Liz has an amazing Excel setup that has to be seen to be believed) but their focus on customers has shone through all my encounters with them. It's great to see they keep looking for ways to use the new techniques to improve their services, Microsoft could learn a lot from them. I know they sent someone to Defrag last year, so maybe I'll see some more implicit web techniques when I do my 08 taxes?