After all the speculation (and some excellent on-the-money guesses) we can now announce that Toys R Us will be the sole distributor of Tomica product in the USA. From the recent press release:

Global toy industry stalwart TOMY Corporation today announced an exclusive first-year retail partnership with Toys”R”Us to introduce TOMICA, Japan’s number one die-cast car and toy train line in the United States. The brand will launch exclusively at Toys”R”Us stores nationwide, as well as online at Toysrus.com in early October. The new TOMICA line promises to bring back traditional road and rail playtime that parents and children love, with improved items and newly developed products for avid fans and collectors to enjoy.

So there you have it. Speculation over.