So far my youtube and images.google.com are a little sluggish because they must have turned on IPv6 which means all my videos and other google traffic are now going through my he.net tunnels.
I figured out what my YouTube problem was today. Well, someone else did actually but if fixed my problem too. Turned out to be an MTU issue. I set "AdvLinkMTU" to 1440 and bingo, everything works speedy over IPv6 now. Here's the list of VARs for OpenWrt's implementation of radvd: