Because if you are, then you are not alone - most of my UK ISVs are only just now looking at SaaS. If you have an "on-premise" model then a move to delivering "on-demand" can be extremely challenging - both technically and from the perspective of your business model. Interestingly it might also be totally the wrong thing to do for you and your customers - and I plan to explore that in more detail in the coming weeks.  In the meantime, take a look at what Gartner are saying.