Keeping track of a projects progress is a common desire and if the project you are interested in happens to be a WordPress plugin then there are a number of RSS feeds which are an important resource for you (replace plugin_slug with the plugins slug!).

http://wordpress.org/support/rss/tags/plugin_slug
http://plugins.trac.wordpress.org/log/plugin_slug?limit=100&mode=stop_on_copy&format=rss

The first of these contains all the support forum posts relevant to a particular plugin and the second is all the code changes that are happening in the plugins repository.

To keep track of these you have a couple of choices.

Firstly you could subscribe to them in your feed reader or if like me you like to receive emails for this sort of thing you can setup a cool tool called rss2email on your pc/server to email you new posts/changes.