I've asked this many times of many people, but I've never gotten a reply. Why do so many people capitalize all three letters of LOW? Shouldn't it simply be Low? Or does LOW actually stand for something?

On promo pieces, whatever's clever. As text, "Low."

For those unawares, the latest release from low* is now available for presale and along with the purchase you get a link to stream the album.  I'm on my third listen and it is very, very good.  IT can be acquired from the Sub Pop website

* See how I didn't capitalize any of the letters... haha!

I understand why someone would do it in a poster. I just don't understand why someone would do it while typing a blog post. 

Another example of this: People always fully capitalize the title of the TV show LOST. There are probably other examples, too. It's a strange phenomenon. Well, strange to me, at least.

ALL CAPS should almost always be avoided and rarely work--but in this case, with a short word, on covers and posters and the like it's fine and fits in well with the rest of the piece. Book and CD cover designers get to break all sorts of "rules" regarding punctuation, etc. to create the affect they are after—as long as it doesn't compromise readability. After all, why bother designing a funky poster if the message isn't clear to the intended audience? 

Lowercase letters were created--along with spaces and punctuation--to make words easier to read. The boxy, horizontal look of A SENTENCE SET IN ALL CAPS is actually more difficult for the human eye to scan and read, and though it may seem illogical to some, using traditional UPPER/lowercase allows you to make the type size bigger than if you had used ALL CAPS.

There are, of course, exceptions. Titles of film treatments, for example, are set in ALL CAPS. I'm sure there are others.

The serifs are unsanned because we like our electron consumption to be conspicuous. Next, you'll be crying for monospace! Get your Helvetacommie ass to the back of the bread line, while we let the serifs wave, like true Americans, for the sake of the children.

Barrett, you are a true patriot! Baci, apparently the space between your ears has been kerned too tightly -- I'd love to know if your talented graphic designer spouse agrees with you.

Actually, a nice combo such as a sans serif headline font and an old style ("serifed") body font provides a nice visual contrast. So, really, can't we all just get along?

Oh and you ludites are allll wroong on the serif thing. IT's b/c your decrepit eyes require guides to the next character. AN OUTMODED METHODOLOGY of information consumption. Serifs are chaotic and extraneous! I'm so serious about this that I challenge you to ...um...some elitist and obscure typographic battle! I suppose this will occur at Carmody and involve beers and Lucinda Console. I know a graphic designer debate!! Hells Ya!! Who is in? Pub Debate: Serif or Sans Serif! GAUNTLET!

I find the all caps helpful when I see/use LOW in print to recognize that it is not a descriptor/modifier.  This is true also with LOST.  Probably should be implemented whenever somebody names their project any adjective.