Yesterday the folks at online real estate sale and data site Zillow were all a twitter (on Twitter) about how they had reached 15.7 million unique monthly visitors in January. That's up 75 percent year over year and a new record. While they touted the merits of their web site, I wondered, no offense to Zillow, if part of it didn't have to do with increasing buyer traffic on the web overall last month. So I asked.

"Off the cuff, I'd put the split at about 50/50, with maybe half of our surge in usage coming from greater Zillow brand awareness, and half from more people starting to show interest in real estate," confessed Zillow's CEO Spencer Rascoff.

"We’re seeing this increased usage in Zillow Mortgage Marketplace as well. Loan requests from borrowers were up 56% from December to January, so that definitely signals that people are thinking about diving into the market."

We also saw a surge in mortgage applications last week in the Mortgage Bankers Association survey, with applications to purchase a home up 9.5 percent from the previous week. The MBA, however, cautions that the previous week had a holiday in it and so applications had fallen accordingly; the two week average for purchase applications is basically flat. Refis are down.

January isn't exactly a hot season for home sales historically, and this year, in many markets, you'd be hard pressed to find any homes under all the snow. Still, the traffic online, where I imagine most folks go before even heading to an open house, is an important sign, as we head into the Spring market. The question mark remains in financing.

Federal regulators are still working on the definition of a "Qualified Residential Mortgage," (QRM), which will determine for which loans banks will have to hold some risk on the books and which they will be able to sell off in securities entirely. That's a pretty big deal, given that Fannie, Freddie and the FHA are still the only mortgage games in town, and a return of private capital to the mortgage world is essential for the future health of housing.

Next week all kinds of banking types will convene at the annual conference of the American Securitization Forum. QRM will be the hot topic, no doubt. It will be interesting to see what the financers of this still-crawling housing recovery think will happen to all that blossoming buyer interest, with a still-uncertain mortgage market.

No doubt there is a cautious optimism in the air, but there is still a very large fence running through today's housing market, with a whole lot of buyers lodged on it indefinitely.

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