Windows 7 is great! I snagged my copy from the launch event and have been using it since 9/28. Aside from a bad flash drive that gave me trouble things have been running flawlessly.
In fact if I open the Event Viewer, for the last 7 days there isnt one single error. Only a couple TCPIP warnings and another related to a print server.
Performance and reliability. I love it. Vista ran solid for me as well. But after a week I would have at least 3 or 4 errors in the EV.
The things I love about 7
Libraries, Jump lists, Live thumbnails & Performance
The things I miss from Vista
Windows Mail + Photo Gallery (Dont care for Live alt) and Windows Search (advanced)
At the end of the day I am very happy with 7. This is my first post so please forgive my rambling