Pladypus, I realize you're apparently new, but realize that everyone here who writes puppetry blogs does it out of a love of the artform. I think that to suggest that anyone is "doing a disservice to the community", simply because they choose not to write about something is rude and insulting.
On a personal note, my definition of "regularly updating" that I use for PuppetVision is new episodes on a specific, fairly predictable cycle, demonstrated for at least 2-3 episodes with the odd random exception. It works for me, but it doesn't have to mean anything to anyone else. If you're suggesting that I don't write about puppet web series just because they don't update regularly you're clearly not reading my blog very often.
I really can't speak for anyone else, but my personal criteria for whether or not I write about something is:
1. Do I think it's good? Is it personally interesting to me?
2. Do I think people who read my blog will think it's good or interesting?
3. Do I have time to write about it?
More of often than not, #3 is the deciding factor.
Bezalel made an excellent point about news vs. opinion (Blink kind of alluded to this too). Blogs are by their very nature more op-ed than journalism. There isn't a single puppetry blog I've read that really meets the standards of professional journalism, though some are more neutral in tone than others.
Certainly there's a need for more voices and perspectives to be heard, but we've also come a long way in a short time. To put this in some perspective, when I started blogging about puppetry four years ago there were virtually no other puppetry blogs or news sites at that time; Will Stackman had a blog where he sometimes reviewed puppet show, Scott Radke had a livejournal for his marionette art and the Puppetry Homepage was updated once and awhile, but that was about it. Today I just counted over 40 puppetry blogs in my RSS Reader alone and I'm sure there's even more than that out there.
If you feel so strongly about the need for a specific type of blog, why not follow the example of Blink and others and just go create it?
I think it's great to have such a variety of voices heard and I say the more the merrier!