I think you're wrong about IBM. Just about everybody knows it stands for "International Business Machines," and if I'm not mistaken it went by that name for a long time before it became popular enough to go by the acronym.

Naming is more important than you think. No doubt a great name won't fix a bad product, and a bad name won't hurt a great product too much, but outside those extremes, I think it helps to have a catchy, unique sounding name, that isn't too ridiculous sounding. If I feel silly or stupid saying a product's name (or an open source project's name), I'm not likely to recommend it unless it's just over the top awesome, which most things aren't.