The classic card is probably quite rare. It would not say "Signature" on it; the annual fee is $39 instead of $59; it has no anniversary bonus; and it earns 2x points only with SWA, not partners. There are no official images of it, AFAIK.
Old Signature card:
The three cards below are post-transition only; you could not apply for them before March 1st.
Premier Card ($99 fee; normal signup bonus: 30,000):
Plus Card ($69 fee; normal signup bonus: 20,000):
New Basic Card ($?? fee;normal signup bonus: 10,000):