A few weeks back I read a rumor that stated the Xbox 360 Pro would be going away.  It seems that some new Xbox 360 Arcade consoles got shipped out with a new box.  In the past there was a guide that showed all the features in the three different console models: Arcade, Pro and Elite.   The new box does not show the Pro in the grid anymore which has lead to speculation that it will be discontinued.

There is a new rumor showing the Elite priced at $299 which is the current price of the Pro and $100 less than the current Elite.  If Microsoft was about to discontinue the Pro and it would make sense to cut the  Elite down $100.  I would assume the Arcade would be getting some sort of price cut as well. 

What surprised me is that by dropping the Pro instead of the Arcade it seems to suggest the Arcade must be selling better than the Pro.  The Arcade model has always been considered the weakest offering in the line because it doesn't come with a large hard drive.  Maybe Microsoft thinks people that preferred the Pro will buy the Elite instead. 

Sources:
http://kotaku.com/5335673/elite-360-dropping-in-price-rip-pro-model
http://kotaku.com/5330287/xbox-360-pro-being-phased-out-pretty-soon