Synfig

[sciboy]

http://www.synfig.com/overview

Sorry to say though that it's really buggy (i mean REALLY buggy) and lacks in documentation, but otherwise is a pretty good application. =)

I am hoping to use it for my 2d work since alot of other applications i've used really don't cater for my methods of applying vector shape tweening to traditional animation.

I'll be adding some documentation to their Wiki later but for now there is just a few tutorials.

[Terro]

I've checked these guys out before. They look promising but do need some work. Their website is always getting stuck on me, lol.

That Warewolf animation in their gallery section is very nice.

[RageArtworks]

It's a pretty good application for just moving vector points, but I haven't seen a way to do frame by frame stuff and that's what every 2D program needs.

[sciboy]

Pfft, the whole point of this application is to avoid tweening frames traditionally.
Why only be mediocre at alot of things when you can be the best at one?
The trick is to prepare any keys and extremes elsewhere (i prefer paper) and then apply it to the vector animation letting the application handle the tweening.

[RageArtworks]

Of course, but don't you agree it's a good idea to just have the ability to do framebyframe. Just the ability.