Time Machine is backing up enormous amounts of data

Since my upgrade from 10.6.8 to 10.8.0 (and at the same time from Aperture 3.2.4 to 3.3.2) Time Machine is backing up enormous amounts of data. With normal use (Google Chrome, Aperture) every hour about 100-200 Mb are being backed up. This was not the case before the upgrades. I excluded all caches from all programs and the Aperture libraries from being backed up. Does anyone know what is being backed up, or how to find out what is being backed up?

Has the Aperture library (what used to be in one package in Aperture 3.2) been split into several packages/folders which need to be excluded now?

Koen