Stopping over at TGB, I discovered Dr. S.A. Miedema's new My Outlook Client for Windows Media Center Beta.  Overall I was very impressed.  Now if my wife wants to know when I have time during the week to run an errand etc, I can show her myself.  

This is beta software and I cannot confirm how exactly he's accessing the Outlook data.  The UI is overall very good though responsiveness lacked in a few areas.

Tons of screenshots and the download here. He certainly seems to have taken a holistic approach to design for 10', even including a triple-tap and full on-screen keyboard.  I also noticed I can access multiple Outlook accounts so if you have your Hotmail or POP3 accounts also aggregated you can check them there as well.

Miedema had a large suite of MCE add-ons including Weather and more.  Now if someone would just build an MCE-based Seattle traffic monitor and Skype client I'd be very happy.