giant says their TCR is a compact frame, cannondale does not.
That's just the marketing department's terminology. Giant calls all their frames compact whether you're talking about the TCR, Defy (longer wheelbase) or FCR (longest wheelbase). I'd consider the CAAD9 pretty close to traditional geometry, by the way.
Basically compact means sloping top tube.
compact frames usually mean reduced number of frame sizes to fit a larger variety of people. "compact inventory" is more like it.
I'd agree with you there....