Yeah, there's an initial hit, but only one DNS lookup per session-or-so if you've got your TTLs right. You're likely to hit hundreds (if not thousands) of asset

Yeah, there's an initial hit, but only one DNS lookup per session-or-so if you've got your TTLs right. You're likely to hit hundreds (if not thousands) of assets in a typical Facebook session, though. Edit: Actually, in Facebook's case, Akamai has a 20 second TTL. But it's not difficult to perform ~1k asset requests in that amount of time... just scroll through a large friend list.