Can two iPhones access the same iCloud content?

My wife and I have iPhones. We have separate Apple accounts on the phones. Can we share the same iCloud music and pictures?

Nope. The same account would need to be signed in on both devices.

You would need to both use the same iCloud account in order to share photos across Photo Stream. You can sync both devices with the same iTunes library to share music, while still using seperate Apple ID's within the iTunes store under the phone settings. (if you wish to continue using separate IDs for downloads)

iCloud does not sync music, so if the end result is to share all music downloads and photos the best advice I can give is to stop using one Apple ID and simply start using the same ID. There is no way to merge two IDs, only to both share the ID that contains more downloaded music and apps.

Now it's possible: You can set up shared albums on iCloud for pictures, and Family Sharing for music bought on the iTunes Store; you can also subscribe to a Family Plan on iTunes Music.