There are a few pieces of information stored in projects which you can't store in the WAV. One is labels (created with CTRL + B, or CTRL + M when playing or recording) at points or regions in the waveform. Even here though, some editors that support an extension of WAV called Broadcast WAV can read and write markers in WAV files (maybe Koz knows more about those than I do)? Another is envelope points:http://audacityteam.org/onlinehelp-1.2/envelope.htm
Note that when 1.4 becomes the new stable version next year to replace 1.2, it will open 1.2 projects but once you save that project in 1.4, it will no longer be openable in 1.2.
kozikowski wrote:If you have a multi-track show (over 2) you have no choice but to try and save the Project. There are no reliable or convenient ways to Export one of those. Sixteen tracks, no problem. Export as eight different WAV files. Ewwwww.
You can in 1.3 Beta (and 1.4 when it comes out) export multi-channel WAV, AIFF, OGG or FLAC files, which gives you a way to save multiple tracks without saving as a project. Multi-channel export is enabled on the Import / Export tab of Preferences by checking "Use Custom Mix" in the "When exporting tracks..." panel. You can have up to 32 output channels for WAV, AIFF or OGG and 8 output channels for FLAC. There is no support for exporting multi-channel files when using File > Export Multiple, though. Nor is there is support at the moment for multichannel playback - a multi-channel file in Audacity will always be mixed down to stereo.