If you're buying another Giant its not an upgrade.
Buy a bike that handles well... some of the comments from guys on the T-Mobile team about their TCR Advanced bikes (while flinging the bike up against the team bus, post race) would make a sailor blush and they reckon that they "lost minutes" on various decents in races last season in Europe.
Spend more on the frame and less on the components. A high spec OCR (or even TCR) is a poor investment because you've got good equipment on a poor ride quality bike.... the equipment wears out, breaks or gets damaged and when you replace it you've still got a a dog. If you buy a decent frame and modest running gear when the wear or damage happens you've got good reason to justify upgrading to a higher quality component and still have a sweet ride.