Ask HN: Agnostic Platform vs. Segmented Approach? or Both?

We are in the process of launching our site/service. We've been through the incubator process. The sales prof's tell you to segment, segment, segment. Get a target market and focus on it like a laser. Classic Crossing the Chasm type stuff -- b/c the idea is that one segment will exponentially grow because of network effects. i.e., focusing on one market segment enables you to build up a brand and product awareness in that niche. People in that niche talk amongst themselves and then you get more market share b/c they refer each other to your service. Contrast this with the approach of focusing a little bit on a variety of segments. You never build up enough critical mass in one segment; consequently, you get less return on your investment of time and energy, and, overall, less total market share. This, in a nutshell, is the segment, segment, segment approach.

Contrast this with what I call the 'agnostic platform' approach. There is likely a better term for it, I'm just not aware of it. Build an awesome product that appeals to everyone. Have your marketing messages clearly spell out the features, advantages, and benefits of the product, but don't segment. e.g., think of some of the successful companies that have done great in the recent past (Twitter, Scribd, YouTube etc.) These companies (at least from what I can tell) didn't segment early on. Facebook, on the other hand, did. They were clearly focused on colleges from the very beginning, and Ivy league colleges in particular.

Finally, the approach we are taking is the BOTH approach. We are building an agnostic platform, but going after specific market segments at the same time.

Any thoughts on which approach is the best? Why? Any helpful experiences/tips in increasing adoption on an open/agnostic platform? I've asked these same questions to MBA profs and others. Most of their knowledge seems tied to traditional sales processes. In their minds, it seems the jury is still out on which approach is the best. I get the impression that they think the both approach is fine, but that we'd be better off if we instead segment, segment, segment.

Hopefully this discussion will help others out who are also in the process of nailing down their adoption/sales strategies.