I got 520 recently some days ago, and I couldn't be so happier. i was so tired of Android, it's buggy, and simply a mess.
I love the design, it's minimalistic, and i believe that it's way much safer... and for a low-cost smarphone, omg, it's so fast, i can't even imagine how more fast are the high ones like 920.
For along time i had my eyes on lumia, but since everyone was saying that was "crap" because it's windows and has only a few apps, i did a research and it's completely bull****. Even if people don't have the official apps yet, there's always some alternatives and even better than the original lol. I'm really hoping for WP 8.1 to arrive and i believe that Microsoft it's going to do his best to make developers do more and more apps for windows, and believe me, i'm seeing many people running away from Android now so it's the opportunity for Microsoft to catch more users and catch the BUZZ, and with all this, automatically developers will develop faster, just give it time. But Microsoft can't stop, and for 2013 I can see they are working like dogs.
I also believe that in the future, WP probably it's going to be the best smartphone, and as popular as IOS or even more?! there's something about Lumia WP, to be honest. i just feel that everything it's so organized and secure as IOS, and if Microsoft don't improve this year, it's going to be a shame. It's a pressure, but they have to catch the opportunity now that the BUZZ is taking over and more people are buying it (running away from Android). I hope developers collaborate for the success.