Investors drooling over the prospect of buying into a Facebook IPO got more red meat tossed to them this week. Over at media metrics rater ComScore (Nasdaq: SCOR), a new report has just come out that bolsters the company's reputation as one of the top providers of video entertainment on the web.

Top dog in the industry, of course, remains Google (Nasdaq: GOOG) and its YouTube subsidiary, followed closely by Vivendi subsidiary and music video specialist VEVO. But the big news this week is that Facebook has just leapfrogged both Microsoft (Nasdaq: MSFT) and Yahoo! (Nasdaq: YHOO) to snag third place in the race. According to the handicappers at StreetInsider.com, this means "Facebook is getting dangerously close to Google ... in terms of total unique viewers of online video within the US."

But if you ask me, that overstates the case quite a bit. I mean, has Facebook made progress? Sure it has. However, according to ComScore, all Facebook really had to do to take third place was grow its audience 3.5% -- from June's 49.7 million "unique views" to 51.4 million in July. Now, perhaps I'm looking at this glass in a half-empty kind of way, but to me, 3.5% growth isn't much to get excited about. Seems to me, Facebook probably owes its higher rank on the ladder more to Microsoft and Yahoo! slipping down it than to Facebook climbing up ...

Google: Still on top
Meanwhile, Google continues to top the rankings in oh-so-many ways. ComScore clocked the YouTube owner at 149.3 million unique views in July -- nearly three times as many as Facebook. Google also leads the pack in the amount of time viewers camp out on its video real estate. ComScore says the average Google user spends nearly six hours per month watching videos on Google (353.7 minutes, to be precise). That's 72% more time than even Hulu clocks.

That's pretty impressive when you consider that Hulu specializes in getting people to click on full-length television episodes, rather than the short clips that predominate on YouTube. It takes an awful lot of "Monkey Washing a Cat" videos to equal one rerun of 30 Rock on Hulu, but all those mini-clips add up.

Foolish takeaway
Lots of folks have big hopes for Facebook when it finally gets around to its IPO. For the time being, though, Google remains the biggest game in town, the most profitable, and at only about two times Facebook's implied market cap, arguably the best value on offer today.

Google's on top today, but will it stay there? Add the stock your Fool Watchlist and find out.