Been waiting for a carrier to shave a bit off the price of the Galaxy Tab before you took the plunge? Well, you now have your first option to consider -- T-Mobile has just knocked $50 off the on-contract price of the tablet, bringing it own to $349.99 for those willing to sign a two-year term (the off-contract price unfortunately remains unchanged). Incidentally, T-Mobile has also dropped the price of the Samsung Vibrant down to $150, although that's not the first time a Galaxy S device has been discounted. Of course, while T-Mobile is the first to start discounting the Tab, it almost certainly won't be the last. We'll keep you posted on any other c