The thing that would concern me most about getting a WP is how far behind it is in the aps department. Not talking about the core things, but aps from vendors of other things. Australian vendors are already behind in the Android dept, so what chance has WP got?
Probably a lot more than you think. The difference between WP7 and WP8 is that the WP8 kernel is the same as that used by Windows 8. With Metro coming to Windows 8, I can see a lot of companies wanting to build apps for it (SBS have already done so). The step to migrating an app from Win8 to WP8 is far far shorter than creating an android or iPhone app.
The take up of Windows 8, especially in the tablet space, will be a driver behind metro app development. If a developer creates and app for Windows 8, it will be pretty easy (and almost a no brainer) to convert that app to Windows Phone 8.
Of course, that's the optimistic side of me.
With Nokia behind it & the Windows 8 tie-ins, it should get a good push along, but the market is a bit catch-22. To get people in, you need the apps. To develop the apps, you need the user base. I dunno, is WP going for an overall market (competing with $49 Huaweis through to S3s), or a higher end market (i.e. iPhone land)? The latter is going to be very hard to crack.
Nokia have a strategy of aiming for the low end, as well as the top end with their WP devices. Essentially targeting volume at the low end, and margins at the top end.
They already have a ~$200 prepaid device (Nokia 610), which while obviously not in the $49 league does provide a better experience.
The upmarket segment they do have a chance, it'll be interesting to see what happens with the iPhone in the next few years and whether they can keep it fresh. I know a number of people who have been iPhone for quite a while are looking for something fresh. They don't really consider app lock in a problem, and since Apple removed DRM from iTunes music their music is also able to be transferred (there may still be some DRM stuff floating about).
There's also the segment of people who've never owned a smartphone (or mobile for that matter), capturing those particular people when they enter the market is key.