This is LED - cutting-edge technology! - not fluorescent, so there's no annoying hum or sickening light quality (there are some reports of noisy performance when the fixture's on a dimmer switch). Plus stupendous efficiency and a long lifetime ("long" as in a ten year warranty!).
Most seem to prefer soft white (which Cree apparently used to brand "warm white"; this has the same bright temperature of 2700K) rather than cool white, which is also on sale at Home Depot.
I just installed one in a hard-to-reach fixture, and the light's as good as incandescent. At this price, there's no reason not to stock up. They'll pay for themselves in just a few years, you'll never have to change them, and you're helping the environment.
Update: the sale's "unadvertised" no more. The new price now appears on the bulb's page on homedepot.com (though it's not available via mail order).