I'm going to offer my two cents on the "search" thing, because it's what I do for a living.
I'm a UNIX systems programmer that works with enterprise search systems all day long. I work with all sorts of data in all sorts of environments for all sorts of clients. Companies spend hundreds of thousands of dollars to purchase search systems that cover less data than some internet forums.
I'm going to tell you right now why people don't use BB search systems: the search systems suck. They're little more than web front-ends to a massive database select. There's a reason you can't do more than one search every 15 or 30 or 60 seconds - it hammers the database, and the servers react very poorly to rapid searches. Databases were meant to store information quickly and systematically, and read it out in a systematic fashion. Random-access searches are a completely different technology.
To give you a point of reference, the text in every thread on this server could probably be condensed into 100MB or less. A search takes a couple of seconds. A search system that has been designed to WORK will comb through a terabyte (that's 1000 GB) of data in less than 100 milliseconds, all while doing human-language translation and interpolation on the search terms. There's also a lot of "editing" that goes into the dataset. This kind of performance and functionality is the "bare minimum" people expect these days, and it's obviously impossible for a free BB to provide it. Hence, nobody uses them! It's pretty logical, people.
The BB search systems are a hack, they don't scale, and they're not very useful because they lack fundamental features any "real" search system would have. To compound the information, your typical user has absolutely no idea how to formulate a proper search query. It's INSANE to expect average people to use this kind of stuff effectively. Furthermore, the search "systems" they implement AREN'T EVEN AWARE of their OWN CONTEXT! The presented results are not thread-oriented, they can't show you individual posts in a thread in a break-out fashion, etc, etc, etc. It's horrible, plain and simple.
They simply give the illusion of a "good" search by presenting the user with a billion different options they can configure in "Advanced Search" - that actually does more harm than good. Searching is tough to implement.
Not only do the search systems suck, the format of the information as its presented and stored sucks. Threads are not stored in any meaningful manner, nor are they edited, and the "good" information must be extracted through hours of reading and reloading threads over and over and over again. To think that the typical user (read: impatient person of average intelligence) is going to do in his head what lots of corporations spend millions of dollars on is to be ignorant of human nature.
From a server performance standpoint, it's my professional opinion that it's probably more efficient for people to post questions and get immediate answers from people who already know answers or know exactly where information can be retrieved rather than hammer the server for 2 or 3 hours (this INEVITABLY happens).
If it's a question of aesthetics, well, then to each his own. The moderators run the site.