Seeing as how you're moving from a data phone to a smart phone, you'll also want to keep security in mind.
It was my understanding that the dodgy apps on Google Play are removed fairly quickly but this article from May tends to imply otherwise:
Malware authors target Android phones. Regardless, I would avoid installing apps from outside Google Play and read the reviews.
A part of your decision should include how you plan on using your smartphone. Sure, I have access to Twitter, Facebook, forums, maps, weather, search, etc., with my smartphone but most definitely don't live on the phone.