The new orkut is much simpler, faster and powerful.
Few changes I noticed:
1. All your status updates will be retained. (The older version can retain only the latest status update).
2. Status updates can get comments (older version didn’t have this option).
3. Finally, the new orkut has got a wall, that is similar to that of Facebook wall. The wall shows the updates like Friend addition, Videos, Photos shared, etc.
You can directly comment on your friend’s updates from your wall.
4. Videos can get comments. (older version didn’t have this option).
5. Got applications for Twitter, Google Latitude, Personalized themes (with the image you choose/upload) and more.
6. Recent Visitors of your profile are shown along with their profile photos.
7. Show more updates, Show more scraps, Show More videos links at the bottom of your wall/scrapbook can load more updates/scraps/videos in the same page inline (just like twitter!)
8. Photo albums can be created / organized more easily with the new interface.
9. All your friends/communities can be viewed from the home page’s (wall) sidebar window, by scrolling down.
10. Video chat comes to orkut too. (previously it was only in Gmail - talking about Google’s services only.)
The new orkut is open only to the invited users.
Checkout some interesting sketches about new orkut here