Throughout AT&T's T-Mobile acquisition explainer this morning, the number repeated most often was 95%. That's the amount of LTE coverage that execs repeatedly promised their T-Mobile purchase would bring to the US. It's a number that's appealing to consumers—and, AT&T hopes, regulators—but don't get too excited quite yet.

AT&T's going to use T-Mobile's existing 1700MHz AWS airwaves to complement (not replace) its own 700MHz LTE spectrum. But this grand 4G rollout is going to take time. Specifically, it will be until 2013 at the earliest that they reach 80% LTE coverage, and they haven't yet provided an estimate as to how long after that it will take for that last, rural 15% to get juiced.

So why flog 95% if we're years and years away? Because one of AT&T's major selling points to the FCC is that AT&T-Mo will advance the government's National Broadband Plan by providing such broad coverage to Americans. The hope, if you're a carrier trying to make a deal, is that the government will care more about that end than they do about the hit competitiveness will take when you go from four major carriers to three, and two GSM providers to one. [AT&T]