My original comment might be a bit misleading. Its actually ok to use tagged relation in a market with a large barrier to entry because then its prohibitively

My original comment might be a bit misleading. Its actually ok to use tagged relation in a market with a large barrier to entry because then its prohibitively expensive to create "spam" entries. This works for Netflix. The problem with the iTunes store here is the low barrier of entry for people to create crappy applications and get them listed.