Pf and IPFW are significantly different these days. I'm sure Scott or Bill could give you a full rundown of how different but for something as complicated as snort_inline (as opposed to snort-inline) I would expect a significant amount of development to be necessary. In addition, it would be a pretty significant feat to make a clean and functional GUI for Snort. There is a reason why there are half a dozen serious UI projects for Snort. I doubt any of the core pfsense developers are interested in punishing themselves in this way when there are so many other things to be done with pfsense.
I totally agree with you. In fact, I ended up my mail saying that it could bring more pain than benefits....
