Platinum is typically considered the best (primest?) of all. then gold then classic. Titanium and all other metals, plastics or compounds thereof, were all made up to sound cool. My x.com TITANIUM visa-check card with its $200 line of credit looked cool, ahem, till they axed the whole deal. You know all those ghetto-ass rap songs (i like rap, shoot me) are talking about platinum this and platinum that. hehe. Amex Platinum, probably still the HIGHEST Rated (RESPECT?) card on the planet, is a good example. Buddy at work has one, they told him "The SKY IS YOUR LIMIT". Scarey thought.
Typically, it's Classic, then Silver, then Gold, then Platinum, then Titanium. But just because it's a Titanium doesn't mean it's better. I have two platinum cards, then got the First USA Titanium card. The platinum cards had $9k and $10k limits on them, no annual fee and nice extras. The Titanium card only gave us a $5k limit, wanted an annual fee, etc. We kept the Titanium card about three weeks and cancelled it. The next card in the line will be called the "Unobtainium" ...