With all of the hoopla in the belief that upcoming Windows Phone 7 device is going to be Microsoft’s saving grace in the enterprise mobile market, this piece from eWeek reminds us that Microsoft is in for a huge uphill battle.

Out of each of the reasons presented as to where Microsoft’s biggest enterprise challenge will fall, the ones that stood out to me the most were the following. The iPhone already has much of the enterprise market. Worse, what the iPhone doesn’t have, RIM’s Blackberry makes up the difference. This is Microsoft’s last chance at doing something successfully in the mobile space. After all, they cannot keep throwing money at mobile forever without seeing a greater return.