Personally, I like the idea, but the subject is rather loose... I mean it's basically build about anything you want to except for German, Italian, and Soviet stuff, lol.. I realize that you'd make the categories rather broad in order to attract the highest numbers possible, but that kinda gets away from the theme at times.. Now this is just me spit-ballin' here, but perhaps a Pearl Harbor GB that focuses a bit tighter? Ships obviously have the greatest number of possibilities, but with the fewest number of modelers... I mean, you can build anything from an aircraft carrier down to a Cap'ns gig... Aircraft come second, but there weren't that many different types involved, maybe a dozen or so.. For vehicles, well... Not much in the way of combat vehicles there for the armor/military vehicle modeler... Staff cars, jeeps, trucks... 'Bout it... Also, I lik Stikpusher, am already involved in several GBs, and I don't want to make the mistake I did LAST year, joining up for so many that I didn't make it on ANYTHING..
For the diorama builders, there's a bigger target though, so maybe you'd consider adding that category, or even making it a diorama GB... (I'm a diorama guy, so I had an ulterior motive for that suggestion, lol..)
You might want to consider delaying it until Pear Harbor Day is more of an "event", like this year was for Operation Overlord, the 65th Anniversary of the Allied Invasion of Normandy... 7 December 2011 will be one of those dates, it'll be the 70th anniversary the "Day of Infamy", so perhaps you could run it from say, 7 Dec 2010 to 7 Dec 2011.. Another significant date is coming up as well, and much sooner... 1 Sep 2009 will mark 70 years since the Start of WW2... All kinds of possibilities with that as GB theme, abeit European rather than Pacific action depicted... To go to the Pacific again, you might consider the events in 1944 that took place in the PTO.. 1944 was pretty busy in the PTO, Truk, Saipan, Tarawa, Leyte Gulf, Peleliu, the list goes on & on...
You could run it up the flagpole and see who salutes, anyway... Give it some more thought, narrow it down some, then try again... Oh yeah, one more thing... It's vacation time for a lot of folks, summer's not the greatest time of year for hunkering down to the bench (unless you're an Auld Phart like me who hates going anywhere that ain't air-conditioned and well-stocked with icy-cold beer)... I don't change my build-habits due of the seasons, but rather because I have no life, lol..
At any rate, I was just throwing some stuff at ya, just to see what sticks...