The operator's VP of partner management Ryan Hughes told GigaOM that it will only preload its own app store on handsets that it sells, although its customers may be allowed to download the clients for BlackBerry App World and Windows Marketplace for Mobile.

It's part of Verizon's push to attract developers of BlackBerry, Windows Mobile, Android and Palm apps, while keeping those platforms' proprietary app stores at arm's length.

It's one of the first skirmishes in what promises to become a rancorous battle in the coming months between operators who are launching their own app stores, and the handset makers who already have theirs up and running.

However, there's still a chance of peace breaking out. Research In Motion in particular has stressed its willingness to work with operators rather than compete against them when it comes to app stores.

Meanwhile, details of Verizon's app store are still thin on the ground, but Hughes says the revenue-sharing model will be "competitive, not only with the price, but with the process and the simplicity which developers have come to expect in open ecosystems."