Well as far as the storage is concerned, I'm a person that likes to put a lot of my music on my phone. I'm a huge rock n roll junkie, and I have hundreds of CDs. Yes, I collect actual physical CDs. I'm not old enough to have nostalgia for vinyl records, and I just don't get the novelty of them today. But anyways, in the past I've dealt with phones that had 2 and 4 gigabyte SD cards. I found these inadequate and had a hunger for more storage. With my last phone, I purchased a 32 gigabyte SD card to hold almost my entire music collection, and certain videos that I would have downloaded at any given time.
What I've discovered lately, is that I just don't need 32 gigabytes. Most of the music on that card is either extremely rarely or never listened to. At least from my phone while I'm out and about. And since I've purchased my Nexus 7 tablet which I now use exclusively for watching my videos, I have even less of a need for storage on my phone. I could cut my music collection on my phone down considerably to 8 or 9 gigabytes and still have more music than I would need to listen to on a day to day basis. With that and some app storage, a 16 gigabyte memory would still have a decent amount of open space for emergencies.
For me personally I think the 16 gigabyte Nexus 4 will be just perfect. Coming from a 32 gigabyte card, I can honestly say I can't imagine myself needing more storage. I honestly think with how much digital storage space has exploded on these devices in the last year or 2, that people have fooled themselves into thinking that they actually desperately need 32 or 64 gigabytes. Now yes, some people might actually have a legitimate use for that much storage, but I think the vast majority of users won't.