Great to see the new Fortune 500 blogging wiki. But I think it seriously undercounts the number of blue chip companies that are blogging. Here's why: Lots of big companies have blogs in divisions. Look no further than us. We write about BusinessWeek and the media industry. But I haven't dared put us onto the Wiki, because we aren't a McGraw-Hill blog. If our colleagues at Standard & Poors launch a blog, they'll have the same issue.
The fact is, blogging is about niches. Big companies have lots of them, and can spawn lots of blogs. Jason Calacanis's blog is counted on the wiki as a Time Warner blog. But he's more like us. He writes about his niche--not much about Dick Parsons or the lay-offs at Time Magazine. Imagine if someone tried to write a McGraw-Hill blog, covering the textbook business, magazines, trades, and financial ratings and info services. It would be a mess.