If you are a big fan of cloud computing and planning to purchase Samsung's latest flagship model, then you might need to reconsider buying the smartphone from Verizon Wireless and AT&T as the two major U.S. carriers have opted out of 50GB free Dropbox promotional offer.

According to official Dropbox customer support page, AT&T and Verizon will not be offering the free Gigabytes of cloud storage to Galaxy S3 owner. However, the reason behind ditching Dropbox promotional offer is unknown. The move seems bit contrary as both these carriers are ditching unlimited data plans.

"Select carriers have opted-out of the promotion on phones otherwise eligible. Unfortunately, AT&T and Verizon are among these carriers not currently participating," said Dropbox on one of Help Center webpage.

The exact reason behind AT&T and Verizon ditching Dropbox's promotional offer is unknown. However, it is speculated that either one or both of these carriers are planning to launch its own cloud storage solution. The local cloud storage solution is believed to go up in second half of this year.

Samsung Galaxy S3 is currently up for preorders at both these carrier, while it will launch by the end of June or in first week of July. Anyhow, the Galaxy S3 will land at AT&T and Verizon after June 20.

The smartphone packs 4.8-inch Super AMOLED display with 720p HD resolution. It runs dual-core 1.5 GHz Snapdragon processor with 2GB of RAM. The device comes with 16/32GB of internal storage with microSD support up to 64GB. In case of AT&T, recent rumors suggest that the carrier is planning to include 16GB microSD card in the package.

The device is available in Europe where the Galaxy S3 owners get extra 48GB of free cloud storage above the regular 2GB bar when signing in through the pre-loaded Dropbox app. In case 50GB of free cloud storage really counts for you, there are some other carriers that will be getting Samsung Galaxy S3. Fortunately, the device is coming to all major U.S. carriers with T-Mobile and Sprint in the list.