I am in Rio de Janiero, looking out the window at the beach... writing a blog.... on Saturday morning. Given how pathetic this is - I will keep it short.
What is a business model? In theory, it is the way a company puts business strategy into action. In reality, business strategies are often implicit, and in many ways are driven by the business models ("that is just the way things are done"). This is fine as long as the business strategy is executing for the stakeholders (even if it can't be expressed).
(In many ways - the line between business strategy, business model and corporate culture are blurred. It makes tough work for a business analyst. More on that on another day.)
Well, if a business strategy is not explicit and business models are driven by "just the way it is done", what is the role of Enterprise Software? I would say the software often time becomes an integral part of the "way it is done", and drives strategy much more than we recognize.
When new software is brought into these situations - espcially if it purports a better way of doing things - two things tend to happen.
One, the model does change and strategy unknowingly changes with it. This is grand if that strategy is a good one. (I will let you judge if vendors sell good strategy - all I will say is that I am not sure it is our role ... ).
Two, the existing business model wins out and the new software is cowed into submission by post processors, pre-processors, adjuncts, core customization, etc. (I would say the most common outcome).
I will say that the ideal is where business software open up the dialague so companies can make the implicit explicit. I think SOA is a move in the right direction... but often times it is used as an elegant pre-processor for enterprise software. It can't turn a sow's ear into a silk purse - but it may turn it into a useful brown paper bag.