I would love to have a "task manager" like Chrome has, not sure how possible this is with Webkit:

I often miss something like this in Safari, when some tab goes rogue and I see in iStat Menu that Safari is using a lot of CPU, but I can't figure out which tab it is - in Chrome I would just identify the problematic tab and kill it and that would solve the problem, in Safari I often have to restart whole Safari to fix this.