I'll admit, I'm a rookie. I've spent a few months now learning and writing PHP...is my effort in vain? Should I ditch PHP and dive into Ruby with a Rails framework?
I like the idea of giving back...if you write a blog you give back. However, if someone doesn't think they will be able to add value with what they would give back, don't do it. There are so many sources of information out there that it actually does get tough to weed out the bad stuff. If you think you can produce good content, write a blog, if not, don't. Very simple.