T-Mobile recently dropped its prices on two popular Android-powered devices from Samsung. The Galaxy Tab, Samsung’s first Android tablet offering, is now available for $349.99 with a two-year agreement; down from $399.99. The popular Samsung Vibrant, T-Mobile’s version of the Galaxy S smartphone, dropped from $199.99 to $149.99 on contract. These new prices appear to be permanent adjustments rather than temporary sale prices, and may help bolster sales as the final weekend of the 2010 holiday shopping season approaches. Sales of the Samsung Galaxy Tab recently passed the 1 million unit mark and inevitable price drops will likely help the device maintain an impressive sales pace. T-Mobile is the first U.S. carrier to drop the regular selling price of the tablet, and it now touts the lowest on-contract price for the Galaxy Tab in the country.