Tom Hollander has a series on how to get MSMQ, WCF and IIS to work in a mulit-server scenario; this is an extension to an earlier post about a pub/sub message bus using WCF and MSMQ.

1. Part 1: basic setup: no security, no transactions, single server
2. Part 2: advanced setup: transport security, no transactions, multi-server
3. Part 3: final setup: transport security, transactional, multi-server

Notice how little you have to change in code, to switch from having your service listen on http to having it listen to a remote MSMQ and supporting transactions. This really shows how robust and powerful WCF is.