I was an Orkut nut for a very long time. Despite suggestions from people asking me to try out Facebook, I hung on to my beliefs that a Google product would be better than any others. I have to admit I was wrong.
Google for me represented everything that was simple, fun and evolving. While Orkut was true to that on the first two accounts, it has not delivered on the third front. It has simply stagnated and even the updates / changes that's being delivered from time to time are just not enough and forward looking.
The very first time I used Facebook, I was literally lost. There was too much going on there and everything looked haphazard. It took me a while to find my feet and I have thoroughly enjoyed my experience since then. I really like the provision whereby anyone could write an application based on the API provided and could make it available to others. A lot of fun applications have been made available and everyday there is something new to look forward too. Even their photo album feature is more fun and easy to use especially when you have to upload a large number if pictures. Plus, there are cool option for tagging pictures, re-arranging them and even making them available to non-registered users.
Orkut has been restrictive and it hasn't evolved fast enough. I guess Orkut isn't a major priority for Google but it has a large user base and it would be a shame if they turned their backs on Orkut and looked for something more exciting.