Evolving Relationships – Technology is nowadays an integral part of businesses in all sectors and the general trend of evolving and de-coupling the dependencies enterprise customers has on technology vendors shows its signs also on the evolution of the way technology is delivered. In the customer's perspective the financial alignment of paying on software as a service and consuming it in a less intrusive method of delivery (ASP, Web Hosting and more Vs. Hard core deployment) presents a step forward in the relationship with vendors. Different methods of delivering software as a service present different advancements in specific industries' vendor-customer relationship.
Independency Illusion – I think that customers (who use enterprise software as a service) that think they can stop working with one vendor on one day and start working with a different vendor on the day after are not taking into consideration: migration costs of historic information into the new system, new training costs, general adoption (Will they like it?) by enterprise users, level of confidence in the old system robustness and more. In real life it isn't easy to switch between vendors even if you have the clause in the agreement.
Development time – I think that this new model enables vendors to bring applications quicker but "dirtier" to the market – Early enterprise adopters who don't care too much for integration, security and scalability can enjoy more innovations in a specific time frame but still bringing an enterprise application to the level where a mainstream customer will be satisfied requires sometimes even more time on development and packaging due to the extra thinking that needs to be done (How do we implement an integrated security scheme with a third party for example?).