Not surprising. I haven't had any battery issues, and I have been getting a lot of calls and more texts than usual. No 4G LTE here yet, but I did have Wi-Fi connected and Bluetooth running 24/7 (too lazy to turn them off because I will always forget to turn them back on).
The display seems to be the biggest battery hog in the phone (which is not a surprise, they usually are the biggest consumer of power, and this display is huge). If you are using voice and quick texts or emails, the battery should last just fine for most people. Games and heavy Internet browsing are another story and will probably make an extended battery necessary. Not that different from any other phone I have used.
Voice calls just aren't that big of a deal. I had over 1.5 hours yesterday and the battery lasted a good 12 hours before hitting 20% (and it only hit that after playing Angry Birds for a while). And I was in an area with bad reception, which causes the battery to drain faster on any phone.
Also, anyone coming over from a BlackBerry will need to get used to the fact that their old phones were unusually efficient with battery usage and data usage due to the way they are designed. The increased features with other platforms come with some costs, and one of those is battery life.