Leveraging tablets to increase WP sales is the best path for MS to take but they are playing a dangerous game.
Windows 8 on the desktop will be a serious adjustment for consumers and very early reviews seem to indicate that. The perception of Windows 8 on the desktop could adversely affect WOA.
Sure it's a gamble, and a risky one for that. But continuing business as usual is IMO even riskier. Possible that Win8 could face the same fate on desktops like Vista did. How that wuld effect customer perception of Win8 on tablets, well good question.
the main benefit I see in Win8-tablets is that you finally get a real computer for the price of a real computer and not an oversized smartphone you can't use to make phone calls for the price oy a computer. But that's just my opinion.
Windows 8 on the desktop will be a serious adjustment for consumers and very early reviews seem to indicate that. The perception of Windows 8 on the desktop could adversely affect WOA.