I have a vanilla server that i play on pretty often with some friends but when i tried to log on today i couldn't see any textures besides item frames and some paintings. I have shaders, optifine and forge installed on a 1.7.2 client and my server runs 1.7.4. I tried disabling my shaders and i even went into plain vanilla 1.7.4 to see if the issue was fixed but it was not. I also tried installing a different resource pack but that did not change anything. This issue is happenig with the default resource pack and all other resource packs.
I'm having the exact same problem as you. What shader pack are you using? I got around this error yesterday by removing my shaders but haven't had any luck with it today.
http://www.minecraftforum.net/topic/2391357-help-cant-see-people-or-block/page__hl__+amd%20+driver#entry28901790