Features
 

1. del.icio.us integration.
2. context sensitive bookmark fields. If I work i want some bookmarks below my toolbar and if I do other things I want other bookmars in the bookmar-bar. Enable this ny having a drop-down to the right at the bookmark-bar. (I might have seen this in Flock).
3. External source-code viewer.(Hey I want to use Textmate to view source).

Otherwise I am very happy with Omniweb!