This. Exactly. But now there seems to be a few tiers of Superstars.
Tier 1 is those shown weekly on Raw (Cena, Awesome Truth, Air Boom, CM Punk, Del Rio etc.)
Tier 2 is those on Smackdown shown on the Raw SuperShows (Orton, Sheamus, Christian etc.)
Tier 3 is those usually reserved for Smackdown (Barrett, Bryan, Sin Cara, Rhodes etc.)
Tier 4 is those shown on Superstars/NXT and not on Raw weekly (McIntyre, Ryan, JTG etc.)
Tier 5 is those shown on Superstars/NXT and not on Smackdown weekly (Tatsu, Baretta, Kidd, Slater etc.)