I've got a new project!
It's called mRemote and is aimed at administrators having a lot of machines to administer remotely. It (currently) supports the RDP and VNC protocols and can store (and connect to) an unlimited number of remote machines.
Here's a screenshot from the first public version (0.0.2.1):

Website & Forum is in the works.
Download mRemote 0.0.2.1You can post your questions or bug reports in the comments until the website and forum is up.