The battle of words -- and eyeballs -- is heating up between online real estate providers Trulia and Zillow.com. Yesterday, I reported on Zillow's press release detailing "record" Web traffic for 2009, noting that it attracted on average 8.2 million unique visitors per month. Not to be outdone, San Francisco-based Trulia came back with its own press release today indicating that 62.3 million unique visitors visited the online real estate last year.

It did not break out the numbers on a monthly basis in the release, but the average monthly traffic breaks down to just over five million unique visitors. (Trulia tells me average monthly uniques stood at 5.5 million). The online real estate company also said that its page views grew by 105 percent, while property views increased by 130 percent. It did not provide the raw numbers for those metrics.

What was even more interesting was Kara Swisher's interview with Trulia CEO Pete Flint. In the interview, Flint noted that he was positioning Trulia to become the first "billion dollar" real estate company -- measured by valuation.

I bet that comment caught the eye of Rich Barton and crew in Seattle since last month I actually floated the possibility of Zillow one day reaching a billion dollar valuation. (One TechFlash reader said that possibility was "crazy.")

But if Trulia has its eyes on that prize, Zillow -- which has raised $87 million in venture financing (more than twice as much as Trulia's $33 million) -- certainly does too. One way to get there is through an acquisition.

And as you may recall, Swisher late last month reported that Google was sniffing around Trulia as a possible acquisition target. (No purchase price was mentioned, though $1 billion certainly seems too high).

Of course, that would have wide-ranging implications for the Seattle area online real estate upstarts. But Flint declined to offer any real hard news about a possible deal, saying only that they are focused on being an "independent company." (What else is he really going to say?)

Zillow is too content on being independent, so now both can try to build up revenues and profits to reach that billion dollar milestone on their own.

Trulia certainly thinks it has a better mouse trap, with Flint saying profits will come later this year. He also offered an indirect slam on Zillow's business in Swisher's report.

“We are not about checking out what a neighbor’s house looks like, but on buyer intent and monetization,” he said.

That's an interesting comment given that Zillow has been ramping up the monetization engines in recent months with its mortgage marketplace, and actually beat Trulia to the punch with rental listings. (Trulia says those are coming this year).

Both companies have kept pretty mum on reporting revenues. But this battle is certainly one that we've enjoyed watching over the years, and will continue to do so in 2010.

John Cook is co-founder of TechFlash. Follow on Twitter @johnhcook.