You can setup smart playlists in itunes as well. I use them to decide what goes on my ipod and what doesn't so I don't have to manually drag files in and out of my ipod.
I have a playlist that only accept albums with a rating of 3 stars or higher. Any album that is unrated, 1-star, or 2-star just stays on my computer.
the way I rate my albums is:
1-star: I pretty much don't like the album, and it's up for deletion consideration
2-star: Album only has a select songs that are worth listening to. In this case, I give a rating to the individual songs I like (giving them a 3-star or higher rating). This way only those songs are added to the ipod.
3-star: The entire album is worth listening to.
4-star: This is a good album that I like more than most.
5-star: All time favorite albums.
generally I have all albums rated, but sometimes I forget with new albums, and so I also have a smart playlist that adds my most recent additions to itunes to the ipod, so those are always accessible while they are new.
It only takes one click to rate, or change the rating of an album in iTunes, which compared to managing what is on the ipod manually saves a lot of time. If I decide to change an album rating from 3-stars to 1-star, it takes one click of the mouse, and will automatically be gone from the ipod on the next sync.