Does my Verizon iPhone 5s have XLTE on it?

How do I know if it does? Would it say XLTE in the upper left corner instead of LTE?

You would not notice, no XLTE as far as I know, XLTE is only available in 250 cities, all east of the Mississippi right now. You could run a speettest.net to check your speed, to see if it has changed.

FYI, t-mobile has the fastest mobile speeds right now ("nation wide" unlike Verizon's new XLTE, which is extremely limited.

No it wouldn't say XLTE on it (at least until a carrier update is issued (if ever. According to Verizon yes the 5s is a XLTE device, though as mentioned it more depends on where you are.

Nope