Hi David,
We have not heard that. Certainly, Microsoft generates a large amount of revenue from SharePoint and my guess is a good 10-20% of that is because of the ability to automate business processes and InfoPath is the best tool for electronic forms to automate business processes in SharePoint. Microsoft has many millions of happy users today on that platform. They have made InfoPath changes to the next version of Office too.
The InfoPath format is also open and companies like Qdabra Software, Formotus, and many others are using it to provide InfoPath tools. Some companies even provide the ability to fill out InfoPath-designed forms without InfoPath. So, even if the investment gradually goes down (as it does with all mature Office products), there is a healthy ecosystem to continue driving features in the product. Of course, that's what we're planning to do.
Hope this was a little helpful. We have been assured by Microsoft that the InfoPath MVP isn't going away anytime soon. That alone seems to suggest that you will continue to see new developments in the future.
:)