2011-02-01 The real pain point of carrier-grade NAT ...
The real pain point of carrier-grade NAT isn't breaking the Internet for your customers...Large-scale NAT could also make troubleshooting harder for the service provider and interfere with application acceleration or even targeted advertising, if an advertiser tried to build a profile based on a shared IP address.It's diluting the value of the eyeballs you are selling. Really classy, Verizon.
"If the guy next to you is into hunting and fishing, and you're not, you might start seeing ads for hunting and fishing," Schiller said.
Source: As IPv4 disappears, transition poses hazards - Networkworld