BTW, judging by the iFixit teardown of the RAZR (and hopefully, applicable to D4) the battery is indeed 'user replaceable' just not easily swappable. I.E. you cant carry a spare around and slap a charged battery in when your first one runs low, but should your original battery loose some of its ummph in a couple of years, it is possible we can put new batteries in ourselves.
DROID4: Rooted and OC Hacked
DROID : SimplyStunning 5.6 1.2 Ghz ULV Kernel
I'm going to do a mini, personal test, today.
I mean honestly, I don't think the battery life will be too bad. I just picked up my Droid 4 yesterday and I really love it. My Droid X has been acting wonky (probably due to the amount of times I dropped it) and I had an upgrade (plus a keyboard is necessary if you need to type out long e-mails IMO).
So far, it's a great phone.
Also, it is a non-removable battery. Obviously you can do it, but it's not covered under warranty. I thought everyone understood that concept? lol
Sony CM-B1201 > Samsung SCH-8500 > Motorola RAZR V3m > Samsung SCH-i760 > Motorola DROID X > HTC Thunderbolt > Samsung Galaxy Nexus/Motorola Droid Razr Maxx > Droid Maxx