blacked-out texture
http://wiki.spiralknights.com/File:Blacktexture.png
missing textures on the yellow/purple spin switches -- the 'shine' effect that these do still happens ok
if i move around a bit the problem corrects itself but it also comes back occasionally
my video card is an nvidia geforce 9800gt and was running at about 66C when this happened (relatively cool for this card)
When it was happening I could reproduce it on that set of four switches very easily just by walking around. Problems like it aren't common that i've seen BUT there's one texture glitch in particular that happens pretty reliably for me:
http://wiki.spiralknights.com/File:Magicbanner.png
As I'm walking by or standing in just the right spot, this sword banner will 'flicker' and disappear for a frame or two. The banner goes away but the sword emblem stays (see screenshot) I haven't seen this behavior at all on other banners, like the shield or alchemy ones down the street. I also notice that when I first log in, the banner is a lighter shade of pink and i got no idea what's up with that
My drivers are AFAIK completely current, updated yesterday in fact from the nvidia website. (driver version 8.17.12.6089, driver date 10/8/2010)
Changing the graphics quality between low/med/high doesn't seem to change how often this happens or make it go away when it is happening. I usually keep it on medium though

It's a shader thing.
It will probably show up in your projectx log as an unable to render warning.
The switches look the same for me, and I've noticed that a few banners look similarly untextured as well. I have a 8600GTX (I think; I'm not on my home computer at the moment). Drivers are completely up to date, though.
Is this something that always shows up on those switches or only on rare occasions?
If it's something you can easily reproduce try and see if there's an updated video driver that would solve it.