Craiglist has been disrupted, it's just not obvious yet. And the world will be a better place for it.
Generally speaking, Craigslist has been "good enough" to not be disrupted head-on. Nevertheless, the world moves on, and the gaps in their product (due to a stubborn obstinate refusal to invest in technology) grow wider and wider. As tablets, smartphones, etc disrupt, and craigslist doesn't invest in those platforms, the feature gap grows wider.
This goes very well with my article on What will kill Facebook. Craigslist is unkillable in a head-on, direct battle. What will kill Craigslist (and Facebook, and Google, and other category killers) is that the world moves on and the category is no longer relevant.
Here, we see the difference between a company like Google, which will fight tooth and nail to stay relevant, and Craigslist, which has never had that sort of ambition and will probably sink (very) slowly into the shadows and be satisfied with having made a deep mark for ten or twenty years. Facebook may be called big and boring, but it's pretty clear which of Craigslist or Google it's more similar to.
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