I also tried Oracle Raptor yesterday. It’s neat, but has a few issues.
The bugs and issues are also listed on http://forums.oracle.com/forums/forum.jspa?forumID=260 . It will do a preety good job as far as helping the developers are concerned. I must point out that the GUI is a lil bit slower.

A free download is now available http://www.oracle.com/technology/products/database/project_raptor/index.html
Found a new ORACLE Q/A site. I think concept is preety neat. Found it on Tom Kyte’s blog.
Check it out at ORA Q/A.