I've just been playing around with Google Trips. As others have said, it's still got a long way to go, but it looks like a very good start.

Most of my bookings do actually end up in my Gmail account, but for those that don't simply forwarding them to your gmail account seems to work fine.

Specifically for Concur, you can configure it to send everything to a second (private) email address as well as the default company address.