The last two pitfalls I see for a succesful WP 8 launch:
1) As mentioned a few times: Hero devices. Flagships. Something to get people excited. Here is where the relationship with Nokia is so vital. HTC has already announced it is repacking their One series with WP, and Sammy is rumored to bring it to GS3 devices and maybe a Note-style Phablet. Those are fine efforts and great hardware, but not unique to WP 8. Nokia will be leading the original, only WP 8, top notch devices. Rumors include a pureview device, upgraded 900- style device in more color options, even physical keyboard devices. That is what is needed.
2) Promote. Push. Advertise. Announce. Exclaim. Bribe. Strong arm. Rent planes with banners, billboards that talk, clowns, water-skiing squirrels, laser light shows, the Rockettes, the Chippendales, whatever else can be thought of. Hire unpopular celebreties to talk about how much they love the iPhone. Link Android to the New Black Panthers and the KKK. Whatever it takes to get publicity and interest to WP 8 and Windows 8 ecosystems.
2013 is shaping up to be a very, very important year for us WP Geeks.....