The above links to an article Toby Wolpe at ZDNet has written on SaaS cloud pricing for which he interviewed me extensively.
Take a look!
I particularly like that he included the following quote:
It may not be in the short term, but SaaS providers will need to show a profit at some point. “That they haven’t got economic models doesn’t necessarily mean they can’t continue as long as their investors are prepared to shovel money into it,” Venters said.