This is an excellent blogging program. I highly recommend it. The people in their forums are very nice and helpful and walked me through every step of the installation process, since I was not very familiar with PHP.
If there are any problems, there is ALWAYS someone to talk to who can help troubleshoot any errors, and members are constantly coming up with great hacks!
You must be familiar with HTML scripting, MySQL, and PHP (to an intermediate extent). I would consider this a "graduation" of sorts from Blogger and Greymatter.
I have learned a lot about PHP configuration from visiting their forums and familiarizing myself with the scripts and installing the recommended hacks.
Highly recommended and less harsh on webhosting resources than CGI scripts!!