I didn't see any slowdowns last week either. It's possible they're getting heavier bot activity. grubmaster mentioned Inktomi one day. That bot is notorious for getting lost in forums and pulling pages too fast.
There's tons of bots crawling around the net. Some folks have software to download large amounts of posts on message boards. These can go multi-threaded and slow a site down to a crawl, but right now I don't think anyone is intentionally DoS'ing. If there is someone trying, frankly he sucks at it.
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