Immediately after you sign up for a free blog you get an invoice for $0. It may seem cute at first, but it's obvious, this will be a pay for service to the tune of monthly fees in the near future. I'll be using it until then.
Don't hate me because I repost (on Realtor.com). ;)
It's certainly a weird way of welcoming you. "Oh and by the way here's your bill, we've waived the fee this time." Maybe they will open it up for others to "buy" into the postings or charge for "featured" bloggers.
Time will tell.
It could just as well be because the billing processes at Realtor.com are a very confused and irregular lot. Either way, that's pretty weird, and I guess we'll just have to wait and see.