I haven't seen JBAS-8907 yet, but I've seen a few others that are annoying for any user trying to deploy an app they got working on other AS's.
https://issues.jboss.org/secure/IssueNavigator.jspa?reset=true&jqlQuery=project+%3D+JBAS+AND+resolution+%3D+Unresolved+AND+reporter+%3D+currentUser%28%29
But I guess that is where the beta comes in and drags out some more of these to be fixed.
And yeah without the file based deployment I basically couldn't get AS7 to do anything in a "developer mode" - only small things deploys fine.
btw. in hope to help adoption we're trying to get a the AS eclipse plugins available in our nightly build updatesite to at do the marker file dance ASAP.