I am currently doing a CUCM 8.0 deployment for a customer. A few cool new little things in 8.0 that I really like that I thought I would mention
1. Just like in CCME, you can now update your personal directory/fast dials etc. etc. from the phone itself.
2. You can reset your PIN from the extension mobility login page.
Just a quick thing around Extension Mobility though: You can't actually perform bulk updates to user device profiles.. This is a bit frustrating and I hope Cisco resolve this ASAP.
Other than that 8.0 is great. There are lot's of good enhancements you can use in your life, the major one being of course the SSL VPN on your phone. How cool is that!