Does the SaaS model really work?  Really?
webwright: SaaS marketing is expensive.  Don't look at 37s or JoelonSoftware as successful models-- they have built in advertising for their exact target market with their blogs/content.Can you spare $500 to find out?  If so, do this:1. Get an adwords account.
2. Research keywords with their keyword research tool.  Are people searching for what you're building?  How much advertiser competition is there?  This will give you some idea of demand (this part is free-- or $5 for the account setup).
3. Build a landing page that explains your value prop as best you can and your pricing.  Have a sign-up button that is BIG at the bottom that goes to a "we're in private beta right now" page with a "give us your email address to get an exclusive invite".
4. measure how many people click on the ad.  Then measure what percentage click on the signup button.  That's a pretty good indication of demand and pricing sensitivity.  The email is a bonus-- if you dash someone's hopes and they still are eager enough that they give you an email addy, then there might be some classic "hair on fire" problems that your purporting to solve.Oh, and +1 for businesses.  I've heard 37s say that the vast majority of their revenue comes from biz accounts.