The categories need a little work, a simple two-level tree with a sensible spread/layout would be good to create that is consistent across the entire site. Currently anyone can create their own Blog categories, so please ignore these. I'm thinking especially about Groups + Photos + Events categories at this time. If you see any major categories missing, please let me know here, and I'll build them as required.
Cheers.
Just added a few categories under Group->News.
Feel free to suggest improvements.