O2 and Carphone Warehouse’s decision to drop the price of the 8GB iPhone has paid off in the U.K. It took only a week for Carphone Warehouse to run out of stock, and it looks like O2 is about to run out as well, according to The Register.

While Carphone Warehouse is listing the 8GB iPhone as out of stock," O2 is showing it as "no longer available," adding more credibility to the rumors that Apple is about to release new models.

Adding more fuel to the rumor fire, Engadget claims it got ahold of an internal O2 memo stating that the 8GB model has been tagged End of Life. According to the memo, "Due to the highly successful sales of the Apple 8GB I-Phone [sic], supply chain have today run out of stock & will not be replenishing stock of this product as it has now gone to end of life."

Despite the apparent lack of iPhones in the U.K., Apple’s online store is still showing a 24 hour ship time. In the U.S., however, Apple’s Web site is showing a five to seven day ship time.

Analysts are speculating that the iPhone will get upgraded soon, too. American Technology Research analyst Shaw Wu commented "What gives us higher conviction in this timetable is that iPhone inventory levels remain fairly lean, which is consistent with Apple’s tendency to wind down inventory ahead of an update. We believe Steve Jobs will likely unveil these new iPhones at his WWDC keynote in early June."

The rumors surround the next generation iPhone range from 3G replacing EDGE, to GPS functionality, a second camera for video chatting, and a case redesign. Since Apple does not comment on unreleased products, everyone will have to continue speculating until CEO Steve Jobs is ready to spring his next creation on the world.