I've run into a strange behavior when I migrated our users from Office 2007 / Vista to Office 2010 / Windows 7 (all 32-bit). They use a web based document management system called NetDocuments which stores all their .doc/.docx files. Generally, when they click on a doc from the browser window it fires up Word and opens the doc. Word has an add-in in it from NetDocs as well so it can upload the changed document directly back to the NetDocs server. I get a phone call when Word crashes, and every single time it has crashed I have witnessed multiple winword.exe processes running in task manager. I used process explorer to see what created the process, and it is all Internet Explorer.
So far I have rolled them back to IE8 and the problem happens less frequently, but it still happens. When I try to duplicate the problem, I can make it happen sometimes if I open multiple documents very quickly. Using lightning fast alt-tab reflexes, I DO see that a 2nd WinWord process is created when a user clicks on a document, then it closes once the document is open. I think what is happening is that the secondary WinWord process that does some sort of NetDocs voodoo is getting stuck open.
This behavior is new to Word 2010 / Windows 7 and google searching isn't coming up with much. I have seen a few posts that this is a known issue in certain circumstances and there is no "fix", but I thought it would good to ask others on this.