I have one releasing at the end of the month.
The only headaches were setup. I didn't use seam-gen or maven and paid the price for it. Setting up a jboss project that way was absolutely sucky, because you had to place the right directories, the right jar files, and still have the right setup in xml. I could do it now better since I overcame those issues, but that was one lesson learned. Do a seam-gen or use maven to alleviate that headache.
Another burn I had was I was using JSP instead of facelets. Do yourself a favor, use facelets. ;)
Another item, are the copious amount of solutions and different ways to do things it can be a bit daunting. That's a good thing. There is nothing you can't do with seam. Groovy, Conversational Beans, PDFs, jBPM, Ajax4JSF, and on and on....Seam is by far the best framework out there.
We are putting the final touches on our website, and I will post a link here when we are done. ;)
Oh one last thing, the Jboss Seam Forums have been a great help.
I look forward to having a look at it whenever you complete the job.
I bet JBoss Seam team has a bunch of successful stories to present in conferences.
Thanks, Pete, I will.
I would put it proudly along with the top 10 reasons of using Seam :)