Short answer: Not likely
They've made mistake after mistake after mistake in the smartphone market--a market they could have owned outright a decade ago, BTW. Their latest mistake is to target the consumer market. RIM was always on shaky ground, and with them collapsing, Windows could have used it's leverage with MS Exchange to bust into the business phone market and expand from there. But, instead, they **REMOVED** IT friendly features from the phone that were present in Windows Mobile 6.5 making it as useless to big IT departments as the iPhone. Stupid, stupid, stupid! Microsoft has a lousy reputation among consumers, and there is nothing in this phone that would make a consumer go "Wow!" They even screwed up that side of the equation. They talk about integrating the phone with Xbox, but native binaries are not supported, so the games run like molasses on the phone. Stupid, stupid, stupid! It's like they are TRYING to do everything wrong. I won't even start with the outdated hardware and "features".
They are way too late to make any real headway in the smartphone market. Consumers will avoid microsoft products like the plague if they have a choice. Especially if it is branded with Windows. Android has already solidified its place as the anti-iPhone. Microsoft has to offer a lot more to push themselves into that sphere. MS **does** have an opportunity to do something in the tablet market, where the ani-iPad is not clearly defined. Metro is pretty cool and may be a hit, but on tablets, not so much on phones.
In short, the Windows Phone is most likely to suffer the same fate as it's cousin the Kin, dragging Nokia down with it. Actually, it will be like the Zune, with crazy fanboys loving it, but the market, not so much. Anything is possible, of course, when you have Microsoft's money, but it's much harder to buy mindshare. MS has a deficit of trust with non-business consumers, and they have to address that issue before they can make any real gains in any other market.
I certainly do not count Microsoft out, but they are not showing the same ruthless ability to turn things around as they did when Bill Gates was in charge. They have been so incredibly slow and mistake-prone with mobile computing that they are climbing uphill to get out of this massive rut they are in right now.