While I disagree with the idea of WP taking over the phone market (sigh, we can dream though), I think they are right in saying that they will finally become a major player. iOS will still have a huge following, because they got in the market early and people tend to stick with what they know. Android will become a geek phone for people who like to mod and change things. WP will then have a strong presence for a good simple phone, and with excellent integration with one's PC and files (still waiting for a phone that will replace my netbook). But to say that they will be the top dog is a bit optomistic.
This is kinda like apple claiming that their R&D was 'at least 5 years ahead of the competition' lol. The fact is that where there is success, others will follow in that same general direction to siphon off of that market. WP will be huge with 8 (mostly due to cheaper licencing rather than it being a quality product), but if they start becoming a competitor with the big boys (which they currently are not) then the Android and iOS will simply change to better fit the perceived needs of the market better.
As for myself, I love WP for 3 main reasons:
1) it is simpler to use/navegate/do stuff on than Android
2) you do not need to go 'through the front door' for every single thing you want to do like with iOS
3) It runs very effectively on slower hardware, which means the phone lasts longer per battery weight. This means phones that finally last all day, or phones that are not as heavy as high end smartphones are.
things they need to work on:
1) slower hardware should translate to cheaper phones, which it has not so far.
2) not having an SD card is a deal breaker for me. I love my free 25GB of skydrive storage, but that is also not going to fit my music collection, and I do not want to rely on my data plan at all times. (WP8 should fix this)
3) I want more integration between my phone and desktops/laptops. Sync my browsing histroy, bookmarks, backgrounds, security settings, documents, etc between my devices.
4) I want more powerful software on my phone. I love that WP7 has a light office suite built in; make it better! Make incentives for programs like peach tree or quickbooks to run on it so that I can run credit cards and make/print invoices or receipts from my phone (That would be AWESOME, even if they are only partially functional). More/better games are a plus as well, but not a huge issue.
5) Allow for more user customization without allowing manufacturer/carriers to customize the hell out of the phone and turning it into the annoyance that is Android.