I was in 4wd to get out of some snow, but when I try to move back down to 2wd the two from wheels on the light indicator keep blinking and wont stop.

Try backing up for a few feet and then back in drive. That will release any torque build-up and the light should go out. Others have noted that theirs will stop blinking after a short time.

That does happen if there is water in the system. In most cases it will stop in a while, when the truck dries out.

Driving a few feet in reverse worked for me on several occasions. It's pretty dry in Arizona, so I don't think I had any water in the system. Maybe it is an intermittent problem with 2nd Gens.

The light turned off, and i'm now in 2wd. The truck still feels really ...um. heavy?

You know how a truck feels more controlled/heavy/sturdy in 4wd. I still have that feeling but it's definately in 2WD. I even sloshed around in an empty snowy parking lot to be sure 4WD was disengaged. Could underneath the cause this? It's still really crappy weather, so i'm hoping this goes away.