Windows movie editor for pc and iMovie for Mac both do a really good job for editing and exporting files to what ever size required. A lot quicker than go studio Adobe premiere pro is the top of the line for professional results. I just use iMovie for iPad super quick just WiFi to go pro app then open in iMovie slide your in and out cut points drop to timeline add music from iTunes export done

When you export to share the movie do at 720p , the easiest way is direct download to face book

Apple Compressor, if you shoot in anything higher than 720 then get yourself an account at Vimeo, allows 1080 uploads. vimeo, Facebook and YouTube are all running copyright infringement software for music and will check the fingerprint of all attached music clips and won't allow uploads unless there are no copyright issue, there's still a lot of music out there that can be uploaded

I seem to remember the instructions saying the Import option in GP Studio uncompressed the files from the camera. Is that correct, if so would need to do that step before taking the resulting files into another movie editor or whatever?

.MTS files produced by GoPros and other camcorders are formats designed to be written easily.
Alas, they are harder (read: need a lot of processing power) to read, and thus directly editing them can be abysmally slow and stuttering in any editor.

Thus a trick is to convert (re-compress) first the Gopro files into a format that is more easily editable, such as mp4, avi, mkv, ... keeping a high quality (high bit rate, a good rule of thumb is to keep the same file size as the MTS files). Note that technically the important point is the actual codec (compression algorithm) used in the "container" file which are the mp4, avi, mkv, ... and it is important to note that most codecs have "key frames" and that a lot of editing software can only cut at a key frame, so re-compression for editing should use very frequent key frames (default is often a key frame every 0.3s).

GoPro studio does this conversion automatically "behind the scene" http://gopro.com/support/articles/why-does-gopro-studio-convert-file-to-the-gopro-cineform-format that's why it seem to edit GoPro files more easily... but any software can do it if you pre-convert the MTS files.

Me, under linux, I use ffmpeg to batch-convert all MTS files with the command line:
ffmpeg -i FILE.MTS -vcodec mpeg4 -b 24000k -acodec aac -ab 192k -strict experimental -loglevel panic FILE.MP4