I really like the iTunes client. I don't know anything about its architecture, but its very “Smart Clientish.“ Little things like the breadcrumbs by genre, artist, and album (circled) make for a highly useable app.
There is room for improvement, certainly. Why can't I search by year, for instance? Why can't I search within a search? Say if I retrieve iMixes with the theme of the 70's and 80's, why can't I search within them for, say, Head East or Till Tuesday? And no wish list or Save for Later feature? No Favorites-type bookmarking feature either.
My biggest problem with the iTunes Client is that its way too easy to click on those 99-cent and $9.99 buttons, but I've been pleased with my self-restraint overall.
