Is Azamara a five or six star cruise ship?

I was having a debate with someone in the office the other day about this. Do people tend to class Azamara as a five or six star cruise line?  I've always tended to class her with other six star lines like Seabourn or Crystal but I've heard other people only class them as a five star line.
So what do you think.................?

I suppose the debate really does come down to how people define a 'six star' cruise line.
What makes one cruise line 'luxurious' and another 'mass market', (for anyone new to cruising and reading this please note all cruise lines are luxurious, the six star lines are just more so).

Like many six star cruise lines Azamara ships are quite small with a 'boutique' feel to them, able to sail straight into the small, intimate ports.
Like many six star lines Azamara don't charge gratuities on top of your bill.
Like many six star lines Azamara provide free wine with your dinner.
Like many six star lines Azamara have a higher than average staff to guest ratio giving passengers a more attentive service.

It's for these reasons that I've always classed Azamara as a solid six star brand but I'm always happy to admit when I'm wrong, (cough, cough). 
So what do you think? How do you define luxury on a cruise ship? Have you sailed with Azamara before and would  you class them as a five or a six star brand? What do think makes the difference between a normal cruise ship and a luxury one? Surley it isn't just the price you pay for it!

Happy cruising