Facebook has taken a beating lately, and its traffic is down 27 percent for the week ending Feb. 23 from a high during the holidays, according to Hitwise. But it's not clear whether that really means bad news for the social network, which has seen an increase in the amount of time users spend on the site.

While Hitwise wasn't sure why Facebook had seen a traffic decline -- the deluge of friend requests and sizeable base of students returning to their studies are viewed as possible culprits -- it did have some good news for the social network. According to Hitwise, the average time spent online has increased 73 percent in the last year. On average, users now spend 21 minutes and 22 seconds on Facebook. 

But Hitwise isn't the only firm giving Facebook a hard time about its numbers. Last week, TechCrunch reported that comScore had seen a leveling out of Facebook's total traffic over the past few months. The site attracted 33.9 million unique U.S. visitors in January, down from 34.7 million in December. But worldwide Facebook grew by 3 percent.

While many have taken to calling the sluggish numbers "Facebook fatigue," the site has always maintained that traffic isn't the measure of its strength, and the fact that time spent online is up for the site seems to bode well for its future. However, CNET columnist Caroline McCarthy chalked Facebook's woes up to a fading cool factor.

"Facebook's traffic may indeed be leveling off, something that should naturally happen after any site's phase of frenetic growth, McCarthy wrote. "Now it's up to the site to prove that it can stay relevant and useful to the base that it's already built up."

Steve Hall at AdRants took a similar view.

"When a shiny new object shows up, everyone at least has to check it out," Hall wrote.  "It's unclear if there's actually a new shiny object out there at this point aside from an expansive plethora of widgetized Web 2.0 goodies, but Facebook's shine won't last forever."