I'd say the biggest difference is simply usability. My coworker uses KeePass and I use 1Password and most things take him 1 or more steps to do than it takes me. For instance, the browser plugins with 1Password are pretty seamless, no copying and pasting just a simple click to login.

However, I tend to think that AgileBits over-charges for 1Password and I still haven't upgraded to the new version since they moved to the app store and tried to make me purchase the same version I had already bought(just to move to app store distribution model).

I bought the family license which gives me 5 users I believe, but I still have to buy the app for all iOS devices which in my house includes a total of 5 devices (at 9.00 a piece right now...that's on top of the 70.00 I spent for the family license). They don't, however, charge for the Android version which I find a bit odd since they charge for iOS.

KeePass does not fill forms, nor store CC info or personal info. It also doesn't have browser plugins (at least when I tried, the Chrome plugin didn't work).

1Password is absolutely essential to my flow as I use hundreds of personal sites and accounts, and in a pinch the 1passwordanywhere html-over-dropbox version is incredibly useful.

One of the biggest features is that when you sign up for a account on a given site, 1Password browser extention will capture that info for you - you dont have to enter it into the UI, unlike with some other managers. This makes it very usable to share passwords with, say, your spouse for shared accounts.

KeePass runs on Linux (I'd happily pay for the better UX of 1Password, but that's a deal breaker).