jimbeetle - 6:30 pm on Jan 16, 2008 (gmt 0)

Thinking about this a bit I don't think ZIP+4 would actually help that much for local search. Even though I'm near the Eastern edge of my 5-digit Manhattan ZIP, it's only about a 10-minute walk to any place within it. (And actually, my ZIP+4 pinpoints my building, a bit too local).

Just too a quick look at Los Angeles ZIPs and they appear to be fairly compact, also.

Now, out in someplace like North Dakota where a 5-digit ZIP might encompass a county, maybe two, well, there's not much out there and folks are used to longer drives.