What are you going to code it in?
Most likely PHP. It's what most people use and what is most compatible with everything, so it doesn't really make much sense to code it in anything else.
Well then sounds good if you ever need another coder I'd be happy to see if i could help!
[offtopic] I recently came across a blogging platform coded in python [/offtopic]
Interesting that Python was used. Python is actually used in many web design projects, but PHP is more standard so it's more frequently used.
I do program some python, so I think it would be nice to try a python based project sometime.
Tags would definitely be the way to go with something like this, as opposed to a more traditional forum hierarchy of categories, forums, and subforums.