So Twitter is down this afternoon.  I've also had problems with Facebook and Gmail today.  Again.  Is it just me or are these guys having real problems with stability?

Imagine for a moment that all the Web 2.0 pundits are dead wrong, and as it turns out, scale on the Web turns out to be a much, much bigger problem than anyone ever assumed.  Services like Twitter, Facebook, and Gmail continue to suffer outages, but their problems get *more*, not less frequent and severe over time.

What would the implications be?

• Would companies like eBay & Amazon (who have largely figured out how to scale) become that much more powerful?  Both have, after all, figured out how to scale.
• Would Microsoft have an easier time selling the relevance of the client?
• What would happen to Yahoo?  Is their infrastructure more important all of a sudden?
• Would online/offline technologies like WPF and AIR become considerably more important to developers than they are today?
• What would the implications be for mobile applications development?

I don't think these problems are impossible to solve… but it certainly is a reminder that stability & scale are an underappreciated challenge for any company delivering their products or services online.