OneQuickGT1- First a little disclaimer: take TOGWT's advice. Do it as he recommends. Don't pay attention to what I do. OK, that said...
Mine seldom get dirty enough to need cleaning, but when I get something nasty on them (e.g., grease, etc.) I usually spot-clean them with Dawn and then wash them in the machine on "gentle/delicate".
I've also laundered then in Woolite with no obvious ill effects, but yeah...the whole machine washing thing seems really hard on them, and it'll speed up their eventual shedding/etc.
You're probably better off washing them by hand with very thorough rinsing, and I never bother drying mine out (just let 'em air-dry, hanging over the edge of the bucket).
I guess it's kinda funny that mine survive such abusive/neglectful treatment as well as they do, but they seem to last a good long time for me.