Here's an example of similar troubles involving the iPhone:
http://forums.ilounge.com/archive/in.../t-200180.html
These users are not as "ecstatic" as some others. And you'll notice in the thread that many of them are having the same problems reported here. That is, sending PictureMail by emailing to 10digits@service-etc does NOT work reliably, especially with Verizon recipients. It's dramatically slower than "standard" PictureMail. Pictures are frequently bounced with no reasonable explanation. You need to know the recipient's service provider. And more.
I've now tested a dozen pictures using "Picture Forwarding" and it seems to work perfectly. It's a little more work than I would like, but not a show-stopper. See my earlier messages in this thread.