This post is going to sound odd but the problem from a network point of view is it wasn't good enough. Over Christmas we had 2 long runners, the iPhone (honestly the model number isn't all that important to about 80% of people

) and the SGS2. The SGS2 has enjoyed a very very good run because its cheap - Samsung priced it EXTREMELY well to networks/shops who could bulk sell for decent returns with virtually any plan and it's extremely potent when you put it alongside other handsets.
If you go into a shop and put the SGS2 in front of people it sells like you wouldn't believe because the screen is both big and crazy colourful. Combined with the decent deals, decent camera, lightness (seriously, no one cares the back is plastic except you guys

) Basically, if you don't want an iPhone or couldn't afford one - you probably opted for an SGS2 this Christmas and this is a fantastic place to be - this is a mindshare winning place. The problem was, Nokia should have been here or at least they wanted to be here but when you slide up the SGS2 to the Lumia problems start appearing which impact the first look.
Out the box, the takeup for WP7 is hampered by the squares/metros huge typeface. A lot of people think it's not as enticing because it looks like it was designed for 7 year olds versus Androids Homescreen/App menu or BB/iOSs App Menu. Yes metro is very nice and all but the initial impact doesn't sell to the mass market, maybe win8 will shift this problem. Before I get people who attempt to moan at me for pointing out UI traits remember that the position I see it from is not the user a single person, but the market, it's a percentage game.
So, we have the Lumia, an SGS2 and probably a BB to decide between and they all share roughly the same price/deal setup, it wasn't ever going to win like this. In my opinion they blew it when they made it the same size as the 4S (remember in a shop you put them all next to each other so size suddenly becomes apparent and the mind naturally compares alike items) and by releasing it so close to xmas but this is just opinion. There's also the issue of pricing, it was priced for mid but they marketed it as high. There isn't much of a market here, people would rather just go higher and be "safe" so to speak or lower and save cash. Midrange smartphones sell OK but the profit is weaker, Nokia did a lot better when they went high price for high end (the entire N series for example) but this had other issues in play - the networks basically forced Nokia to under price it because they knew it was going to be rough launch - no market share, brand loyalty going out the window over the last 3 years, networks are risk adverse.
The register is claiming it got outsold by 100 times to the SGS2 - this is unlikely, it didn't get that smashed, but it wasn't close. BB did well though, good to see the new models selling as well as they did.
Super edit: I really liked mine though, haters be damned. WP7 is just different.