"The new Google Apps Premier Edition costs $50 per user account a year. It includes around-the-clock telephone support, and 10GB of storage per user compared with 2GB. The new edition also includes a guarantee of 99.9 percent uptime for Gmail and application programming interfaces that businesses can use to migrate data, enable single sign-on and do other integration.(News.com)

10 GB and 99,9 % uptime garantuee ? Sounds like a good deal at 50 USD per user. But I'd still use the free version if a company doesn't get too big. Because the service is already great in the free version. Okay, no round-the-clock telephone support, but I needed the google guys once for a domain related issue and it was all fixed within 2 hours.....
Google Apps Premier Edition Launches - One Small Step Towards Google Office