Along the lines of smb12's EUA tracker, I've recently been working on a fare bucket database which monitors CO flights for the week before departure. It tracks the fare bucket availability for a set of routes, and aggregates and graphs the data.

My hope is that the data will be useful for picking flights which provide the highest chance of an upgrade (ones with higher average Z availability) as well as flights with a high probability of a bump (ones with lower average Y availability). I've also put up graphs for a few other queries, such as which day of the week has the highest availability, which hubs provide the highest availabilty from a given city, and overall average fare bucket availability.

Feel free to check out the website at http://joshua.cs.rice.edu.

While testing it, I've only been collecting data for a few routes (IAH<->EWR, IAH<->SFO, and IAH<->MSY), so these have the most data. I've recently added a good number of other routes, and the data for these will slowly trickle in.

Let me know if you find it useful, and please send any comments or suggestions my way. Thanks!