The signature when released several years ago required a 710 fico score. If you don't get that they will consider you for the regular visa plat and then if not that down to the store card.
They usually don't give you tier 1 right off the bat but if you call and argue that your scores should qualify you for tier 1 interest and that's what you want, they will usually move you to it.
When the signature first came out, they approved us for platinum instead on tier 2, I called and said the only requirement was 710 and (oh forgot, think it's 80k salary) and that I wanted signature, which a supervisor quickly issued, then I said if I qualify for the signature I should qaulify for tier 1 interest, which they also quickly changed. I LOVE NORDSTROM, wish they would have let me carry it through bk, I was planning on paying it