It depends on your needs and budget/funding.
If you're self-funded and don't have particularly deep pockets, then office space & lease is an overhead and commitment that could be keeping you from spending on more core aspects of your business. Not having one certainly cuts the burn rate and keeps you in the game longer. Home offices cut out commuting, that's time and stress saved. It can also let you draw from a much wider talent pool. That brilliant ex-colleague who lives three hours away is far less likely to join your startup if he has to sell his house and move his family to a new city.
You'll have to balance this against your team's personal needs. Some people can't work from home because they need the social interaction, or it's just not a very conducive environment for doing work. Some need the work-home separation, although if one needs that, the all-consuming nature of a startup is maybe not for them.
Equally important is team dynamics. If your team is a group of people that have never worked together, then the isolated nature of working from home could be counter productive to get the team to gel and stick with it for the long haul.
In our software startup, we work from home. Any face to face meetings we do, we do at home, but they're quite rare. We do all our communications over Skype, padded out with a Wiki and some other software. I blogged about that here, showing how you can roll out decent infrastructure for almost no money, that is well suited for working from home.
Jeff Atwood blogged about his experiences developing software from home here.