The Office is a pretty seminal work for a certain generation of television watchers (in ten years there will be nostalgia for it the same way there is for Friends now), so it's kind of a no brainer that NBC would want to revive the series after its absence from the airwaves.
What is weird is that none of the original cast members seem to be coming back. According to THR, NBC is looking to reboot the Dunder Mifflin misfits with creator Greg Daniels attached, but this new iteration will feature a whole new crew. In fairness, no one from that original troupe is probably available (certainly not Steve Carell), as The Office ended up making stars out of folks like John Krasinski (who is now Buff Action Hero John Krasinski Who Fucks to you).
The reboot is obviously just more of the latest IP craze that's taken over both film and television (and given the recent success of Will & Grace's comeback, NBC's looking to strike gold again). Sometimes these things work out for the best (Twin Peaks), but for something like The Office to be a hit, they'd need to duplicate the chemsitry the comedy's cast genrated. Granted, its been done twice - as the American verison is nothing more than a smart reboot of the Ricky Gervais British comedy of the same name - but seeing lightning strike for the same property three times in a row is highly unlikely.
This is all still in the very early stages of development, so it may never happen, but I bet Rainn Wilson lobbies hard to get a new paycheck, as his landlord's probably calling.