There just seems to be no stopping the guys in the CRM product teams these days! The next part of the business productivity Accelerator has been released!
There has been hints at the new Auditing functionality coming up in some of the already released Accelerators (like the eService module), but now there is a full Plugin Based solution available for you to download from Codeplex: http://crmaudit.codeplex.com/Release/ProjectReleases.aspx?ReleaseId=26998
The plugin allows field level change auditing and can be quickly installed & configured using the plugin registration tool & importing the entity customisations field.
Happy Auditing! :)