InfoPath Dev

I created a form template in IP 2007 a while back.  When it was created, I saved it as InfoPath 2003 Form Template so it could be accessed by those with IP 2003.   I now want to save it as IP 2007 version as I no longer have to worry about a user only having IP 2003.   I have re-saved the file using the "InfoPath Form Template" choice available under Save As. 

I want to be able to use the file with SharePoint 2007, SharePoint 2010, IP 2007, IP 2010; I know all users have at least IP 2007, some have IP 2010.

Are there any behavior changes / problems I should be concerned with in using the new version?

To the best of my knowledge, just saving it as IP 2007 shouldn't cause any behavior changes.  Making it a 2007 form just gives you access to more features.