I have heard that some say the battery life is unusually short though. Does anyone have any opinions on it?
This entire subject is subjective, but:
I just got an HTC EVO 4G. Yes, the battery life is short. As long as you arent a heavy user, or away from a power outlet for more than 6 hours, its not a big deal. I have a desk job, so it's fine. I can just plug in while I'm at work if needed. Oh, and I came from an iPhone.
If you are coming from a plain old phone that just makes calls -- then yes, the battery life sucks. If you are coming from an EVO 4G, then the battery life is improved. Haha.
Does it seem like something that would be worth two years of use if purchased today?
Again, this is subjective. For me, I've had a smart phone since about 2001, so I cant imagine even having a regular phone without email, internet, music, etc... So yes, I think it's worth it. For my mom, she thinks anything more than just a phone that makes calls is a waste of money, so no, it's not worth it. It all depends on how useful those features are to you, and what you are willling to spend per month for it.

That's kind of like me asking you if it'd be worth it for me to buy a pick-up truck or not, if you know what I mean

Everybody has different needs/wants/likes/preferences.
For *ME* though, it's def worth it. And the incredible is a great phone. However, it has almost been out for a year, and for a cell phone, that means it is nearing its EOL (end of life). So having to use a cell phone for 2 more years thats already a year old is, to me, unrealistic. But to others, not a big deal. I usually get a new cell phone every 12 months. I am a tech-geek though. Not everybody cares about cutting-edge.
Oh, and if you can wait a few months, there is a whole slew of new smart phones coming out that were announced at CES.
Good luck!