InfoPath Dev

Most users in our environment have InfoPath 2003 on the desktop.  A few managers and developers have 2007.  We are running several SharePoint 2007 Servers hosting a large # of InfoPath 2003 forms.  The forms will need to connect to databases and web services.  In order to avoid a maintenance nightmare is there anyway to share a dataconnection so we can make the update in one place when database environment changes or am I forced to go into every 2003 form and make the updates there?

Yes.

MS has anticipated this. In SP2007 you can create UDC's Universal Data Connections.

With 2007 you can browse and select them.You can also convert existing DC to UDCs in designer.

 You could use InfoPath 2007 to create a UDC library and then update your templates to use these.

Then all forms share data connections and they can be changed outside of the templates.

The Database Accelerator from www.qdabra.com might also be interesting to you.  It allows all of your forms to be databased and has the tools that make migration and administration much easier.  Once you get a lot of forms I am sure you understand the headaches.