In my new book -- see preview on Facebook -- I isolate five conversion signatures, one of which is right for your website. One is the Site as a Service signature, and the first conversion strategy is "Turn Visitors into Tryers."
This case study bears out the importance of that strategy. SaaS sites have an advantage over ecommerce sites in that their visitors can try the product right there on site. Why not offer a trial? Find out the other strategies in a free video introducing the book's core concepts.
This article does a great job of explaining the thinking behind testing at Airbnb. Homeaway and other competitors better be doing this kind of work, too.
For those of you who are testing, this article gives a great overview why you should test longer before calling a winner.