Sarah Perez over at ReadWriteWeb has a great piece detailing the abundance of [Lifestream/Twitter/MosSoSo/Social News/etc.] offerings out there.
To me the most obvious cost to getting involved with a lot of these applications + services is the time it takes to properly evaluate them (and the opportunity cost of not having the time to do something else – like driving around Liberty City trying to make a break for Algonquin)
The biggest challenge is not only finding the ones that work best for you (or quickly recognizing the ones that don’t) but also trying to predict the ones that are going to be around for the long haul and stand the best chance of getting some uptake with your friends that might not roll in the same techno-circles as the Scobles and Winers of the world.
As I keep adding services to my day-to-day life, the challenge of integrating new ones becomes greater as they invariably begin to overlap (see dodgeball and brightkite).
On the one hand it feels like a great time to be a startup trying to get going in a space yet on the other hand, most of these spaces are so over-saturated at this point that its really difficult to get a potential user’s proper attention.
