Ok OpenStack is worth sitting up and noticing, it has huge potential, pre installed frameworks for a lazy mans hosting, wonderful.
From my experience as a web:
1) transferring files via FTP, both key and path to file location set-up in my install was a pain to get sorted, and probably made worse by the fact that I did this on a windows machine so I had to do a number of installs before I could connect.
2) Getting a domain name exertion to the install / gear is a pain, there not much help for http://www but your ok if you want a cname but thats not everyone's ideal set-up.