OK, it looks like my pre-exam nerves were unwarranted!
Just passed the 70-647 with a 910!

This is the final one which earns me the MCITP : Enterprise Admin cert.
The exam was very straightforward, so much so I was worried I'd missed something.
Thanks very much for the support from people on this forum, especially dfosbenner who helped calm me down.

Now for a nice break from certs for Christmas and will move onto 70-680 (Windows 7) in the New Year, followed by 70-432 (SQL200

later on.