If you’re rolling out a new smartphone anytime soon, Compete says the formula for success is to keep ’em guessing. According to recent research, Compete found that the Droid’s strategy of a well-hyped but vague announcement, followed by a long trail of crumbs that lead to launch day, kept consumers engaged and waiting for the final coming of the device.

Compete’s research compares traffic to “micro sites” for both the T-Mobile G1 in April of 2008 to that of the Droid from time of announcement to time of launch. 

“The hype around the pre-launch around the Droid was considerable, so we were looking for a fairly unique way to measure some of the pre-launch buzz,” says Elaine Sanfilippo, director of consumer technology at Compete.

What they found was that announcing a high-profile device and then just leaving it for the bloggers, journalists and analysts to pick at, is not enough. “There’s a trend here that the more information you give out, the more frequently, the more you’ll see an uptick in your pre-launch Web site traffic,” Sanfilippo says.

The findings of the report could have some interesting implications for the marketing strategy employed in smartphone rollouts. Brace yourself for more smartphone announcements that are devoid of details. According to the report, traffic to the two device’s sites was comparable at each phone’s announcement; however, Verizon Wireless’ slow leak of information made for almost double the traffic generated by the G1 on launch day.

“When you actually look at the launch numbers, the Droid had double the online traffic that the G1 had,” Sanfilippo says, adding that seasonality factors, marketing budgets, as well as the differences in available audience at Verizon and T-Mobile figure into the results as well.

However, Sanfilippo says that relative percentages can be more telling than absolute numbers. “You could have a great absolute launch, in terms of the number of eyeballs that looked at your device, but if that’s only half as much as whatever the last popular device was, then have you achieved anything new? Probably not,” she explains.

T-Mobile announced the G1 a month before launch and just kind of left it at that. The Droid kept things a bit tighter, announcing 20 days before launch and then “priming the pump,” so to speak, with pricing and other details along the way. According to a blog from the folks over at Compete, “the shorter duration of time between announcement and launch, coupled with a new announcement midway through the wait-period, served to reinvigorate interest and keep the Droid in the minds of online consumers.”

“One of the things that we found, and this is true of the iPhone and Pre launches as well, is make a big splash with the announcement, but then keep feeding the public information because that gives them reasons to go back and stay engaged,” Sanfilippo says.

Ad Age estimates Verizon spent $100 million on its Droid campaign, which may be the most the carrier has ever budgeted for a single campaign. Initial estimates for first-week Droid sales are hovering right around 250,000, which probably means someone did something right.