You don't have to wait for your IT department to wrap your back-end application functionality into real Web Services, you can "cheat" by extracting data in the form of reports and turning them into RSS feeds, which you can mash up with graphical user interfaces and tools.
Clearly these mashups aren't going to be the killer apps Hinchcliffe notes are necessary for mashups to become a valuable enterprise tool.
Sorry, IT run-around crowd (Seybold's term) but any mashup vendor saying you can bypass IT and get what you need through RSS feeds, screen scraping and widgets isn't considering that you will need access to back-end enterprise services to get the most out of your mashup investment.
Let's consider an example. Let's say your sales manager wants to keep track of important news cross-referenced to either existing accounts, or opportunities in the pipeline. This could be put together by mashing up CRM data, available through reports and screen scraping, with RSS news feeds, all without the help of IT. That would give the manager some great data, but he can't do anything with it unless he hops out of the mashup and into the CRM system.
The real killer application would allow the sales manager to action the data within the mashup. So, for example, if the manager sees that a company in his pipeline just hired a new COO, the manager could push a button to create a TODO item in the CRM system requesting the account manager arrange an introductory call with the new executive. That sort of interaction isn't enabled by RSS feeds. It is enabled by services connected to back-end systems controlled and managed by IT.
What mashup platforms will do is reduce your dependence on IT to construct new applications. IT can take on the role of a trusted partner rather than gatekeeper, but you still need them. Any mashup vendor who says otherwise doesn't understand your business.