I don't know if this is simply a placebo (I hope not) but I felt like the latest build 1.0.1959.0 is substantially faster than the public release build...(im also in the connect group)
As far as i know, the only noticeable in your face change in the newer versions is different help files, and different "did you know" comments for the update tab. Besides that, or perhaps besides the possible performance improvements, there aren't any changes.
Btw, it is possible to download the 1.0.1676.0 build from the connect website if you are in the group. Im suprised nobody has posted a download link for it yet. This version is different from the public release in that, if you click on the carrot on the "help" button in the upper right hand corner, you can upgrade the version to the latest: 1.0.1959.0