I haven't been an upgrade critic in the past, but a lot of people I know have switched from the iPhone to the Samsung Galaxy S4...gorgeous 5" screen, huge 13MP camera that takes really nice photos, NFC, 2GB RAM, etc. So I've seen a lot of those floating around, and one of my coworkers just got the S4 active, which is water-resistant. Boy would THAT be handy! So I think a lot of people are feeling left out with all of these Android upgrades...and then Apple comes out with a gold 5 with 110% more fingerprint sensor. So, it's kinda meh.
And the surprising thing is, I'm seeing a lot of hardcore Apple fans switching to the Galaxy & other types of Android phones. Like, people who I thought would never switch ever. Personally I like the iOS platform since it just gets out of your way with no fuss, but it's hard not to get jealous from a waterproof phone or a phone with a huge 5" AMOLED screen & 13-megapixel camera, you know?