Well, it seems like it has the potential to get out of hand with the humor opportunities and I'll admit I'm guilty of that already (I was just seeing how it worked!)
The problem with this sort of thing is all the spelling people are likely to use. For example:
All would be different tags even though they're the same thing.
I'd suggest something like MLBTraderumors.com has. Each post is tagged with the player's full name and teams involved. So "cliff lee" is a tag and "texas rangers" is a tag. Couple that with subjects like "RISP", "Sabermetrics", "clutch", etc. and one could have a pretty effective tagging mechanism.
I wish the tag cloud could be displayed in a sidebar. I think that helps encourage more precise tagging and searching.
The funny tags are funny and all but they aren't very useful. It may be that the tags need moderation or a guideline or both.
"Bring on Rod Stupid!"