Replacing low res album artwork in mini player

Here's a slightly neurotic question for the iTunes album art lover community....

I like the new miniplayer in iTunes 11.04 very much. The problem I've discovered is that much of the album artwork I once added to iTunes 10 and which looked fine in the defunct cover-flow, now is too low res in miniplayer.

I've gone back and chosen the artwork over again - usually on the fly when a song comes up in the mini-player - I drop the new artwork onto the miniplayer pane, and bing - the album artwork now looks great.

The problem is that the artwork only seems to be replaced for the one track of the album. All other tracks of the same album have the same low res artwork associated with them. Wouldn't it make sense for the artwork to replace for the entire album with this simple move?

Does anyone know why this is or if there is a good workaround for it that does not involve me stopping my workflow and right clicking to "get info" on the track and replacing artwork for the entire album?

Thanks!