[TheMilkCarton]

Form Hack. It's a mess to work with, but if you get someone that knows what they're doing to work with it, you can create a really nice template for the first post.

It does exactly what you want. You tell it all the different fields, provide the layout, and you can even require that everything be filled out before it posts.

Then you could also install the hack that keeps the first post on every page if you want it to act like the modifications threads. (Sorry can't remember the name offhand)

No need to code anything new. You already have all the tools to do it.