Right now 100% of my startup team is remote. There are definite advantages, but as far as we are all concerned we think the disadvantages outweigh the advantages. Why?
Because the communications mediums available still do not give the resolution we need to communicate optimally. Even with Skype/join.me/freedcamp etc... the turn around time for decision making is orders of magnitude slower with remote teams than it is with co-located teams - especially when you are on different time zones and in different continents.
A perfect example is when we wanted to implement a design and UX change on our beta website. The change came at my request after visiting a customer and went to the CTO and the design lead. The CTO started working on the back-end about an hour after I sent the message, but it was almost a day later that the design lead got the message because he was 8 hours behind. We needed some of the design pieces before the front end could be finished and tied together with the back end. About a day later the design lead finished the design and committed the change. At which point it was midnight US time so another 8 hours till the commit could be integrated. We realized we needed a slight change so we had to repeat this process. The whole thing ended up being a couple days for something that would have taken maybe two hours total had we all been in house.
These lags add up very quickly and have pushed something that would take a day of turn around to nearly a week.