Songs Not Showing Up on My iPhone

Strange problem I'd like some help with... songs not showing up on my iPhone 4 (in any way, including iCloud), but are showing up on my wife's iPhone 4S and Air Book and my iPad 2 and iMac.

Here's the breakdown (I'll be specific):

1. Playlist title "The Decemberists" created on iTunes on iMac and I added 7 of 10 songs from an album.

2. Playlist title shows up on both my and my wife's iPhone.

3. Wife's iPhone shows all 7 songs in playlist and available for download from iCloud (if the song isn't already on her iPhone)

4. My iPhone shows only none of the songs

5. When I check iCloud it shows the 3 of the 10 from the album NOT on the playlist available for download.

This is happening with multiple songs, not just The Decemberists (so it's not my iPhone critiquing a particular band).

I've tried the delete from my iMac and then re-download option... didn't work. As I said, this isn't an issue on any other Apple device we have, just my iPhone.