When the satire gets way out in front of its target.

Huffington's Toast is not only far better than than The Huffington Post, it doesn't even really need The Huffington Post to continue to exist -- either as a real site or as something anyone pays any attention to. The Onion initially based its format on USA Today, but is no longer at all dependent on USA Today as a subject of mockery. Similarly, the Toast doesn't need the Post. The format accommodates satire of all sorts of bloggers, celebrities, and politicos, and they can keep going on that material long after the Post is toast. The Post was useful to get a snappy look and a flood of attention, but these guys have already run right past it and become a general humor site.

Judge for yourself, because I'm a running joke over there, so I must be biased. But which way am I biased?