I don't choose to have a small computeer either, but that doesn't hcange the fact that there are very good reasons to have a small motherboard. HTPCs, dedicated lan gaming systems for people who don't wanna drag a full tower to lan parties, 1U servers, plasma display engines(which I'm still learning about to help a customer, dedicated computer systems for Plasma displays, for uses where a company used to use a computer hooked to a projector).
And as we've already stated, it's up to the motherboard manufacturers whether or not to use them. It's not like Intel is saying here's BTX, everyone has to use this standard or you're going to rot in hell for all eternity.
There are computers now that don't fit the ATX standard(in normal, micro or extended), ie ITX, NLX, and sure there are others.
Intel is trying to set a new standard that allows increased airflow, and sizes better to smaller systems. Think half the reason people are complaining comes down to two reasons, neither of which is a really logical reason to dislike introduction of BTX.
1. They just dislike Intel. Such is their choice, but rather foolish reason to immediately dislike BTX.
2. They prefer ATX(either because they don't want to have to replace stuff they already have, or jsut prefer it for some reason). That's all well and good, but no reason to complain about introduction of a new standard for those who want it. I kept an AT board until just a year or two ago. I prefered a hardware power switch on the front of my case in easy reach. Coulda sset that up with an ATX system, but had no reason to. Had a perfectly good AT case and power supply that had served me for years. Does that mean I badmouthed ATX, or complained about fact it had been introduced? No, quite to the contrary, built tons of computers with it for various customers/jobs, and enjoyed fact I was no longer threading that frigging power cable to a front switch. Will I upgrade to BTX when it comes out later this year? No, again, I have a perfectly servicable case/psu/motherboard that I jsut bought earlier this year, and have no interests in replacing all that again. Does that mean I'll complain about BTX? Nope, and will probably start using that for new builds again, at least for builds from scratch, probably not upgrades for a while though, unless the customer really wants to add in cost of the extra components that will require replacing.