As for the problems of the maintenance required to run the planet, well, there's an obvious answer to that one, isn't there?
Yes, robots. It's the Space Year 2009 and there's no reason robots can't run things while we're hibernating. Not everything of course, but we'd just need basic life support going - heat, energy and so on. Perhaps pizza delivery. If Big Trak can bring me an apple back in the early 80s, robots can run a power plant or chase rats out of bins in 2009. No problem at all.
It's not like a zombie apocalypse or a plague scenario because that assumes that the area inside residential dwellings are up for grabs too. But they aren't in the hibernation plan and that's a massive difference in the available surface area for cruel, cruel nature to take hold. And then, outdoors, every year we'd have the March Spring Clean. A festival week before we return to real work where we all get together and make the outdoors inhabitable. Due to the months of little human contact, the March Spring Clean would be a great way of getting us used to other people again and would provide a warm and fulfilling bonding experience.
A treat for the soul.
See, there really is no down side.
And from November through February, we'd all rest. Play games. Sleep. Read some books. Sleep. Watch a few sitcoms. Sleep. And so on. We'd make our own heaven.