Hmmm... OK, mea culpa that I didn't know it was OTS software (never heard of Jive before tonight), but let me clarify my point. Looking at the new interface, I see inefficiency. Tall rows for message title/icon/etc, pretty colored icons to choose a forum, non-scalable width, wide column for "Top Participants" and such.
The software I had in mind was vBulletin. I see that used on many of the forums I frequent and it seems to be very efficient and easy to use.
If Adobe has to limit the window width and still display additional information, Apple's Discussions pages seem to do that pretty well. I don't know if they are using proprietary software or not (I'm guessing yes) but that seems like an efficient use of the space available.
I'd love to see the forums concentrate on legible text, a logical hierarchy of forums/folders, and easy robust editing (like the ability to include in-line images and attaching files). I don't need fancy graphics and other bandwidth-hogging elements. Heck, look at Craigslist. Low bandwidth, very efficient, easy to use.
I'm not suggesting that any one of these is the best for Adobe, just that there are more efficient forums out there. I don't know much about Jive, but looking at the examples on their web page, they seem to concentrate on a pretty fluffy UI. However if configured appropriately they can do a pretty good job. Take a look at the SAP site that uses their software: https://cw.sdn.sap.com/index.jspa
RE: Adobe designing their own software... NOOOOOO! They need to put their resources where they do their best work.