How does one say the year in Latin? Does one say the letters or the word that the letters stands for? Are some numbers pronounced in reverse order, as in German?
The Romans would indicate the year in two ways: By the consuls in power (in the consulship of ___________________) or from the founding of the city (ab urbe condita). I do not know how Medieval Latin did it. I imagine Anno Domini.
Examples from Eutropius: “M. Tullio Cicerone oratore et C. Antonio consulibus, anno ab urbe condita sexcentesimo octogesimo nono.”
See http://en.wikipedia.org/wiki/Ab_urbe_condita
Just stick with MMIX 
No, I mean, How does one speak the year number? For example, in English, I would speak 1984 like this: “nineteen eighty four.” How would one speak the year MMIX, Latine?
Well, if you just want to say 2009, you say duo milia novem, but I do not know the particular formula for the year after the fall of the Roman Empire. One could just keep counting from 753 (AUC) and get 2763 AUC (if I am remembering correctly. I think you simply add 754 to the year).
Oh, OK, comprehendo, gratias.
Adrianus,
So, you use the ordinals? In the two thousandth and ninth year of our Lord.
Yes, normally you do for the date.
Ità, sic plerumquè tempus das.
I think it would most naturally be said as an ordinal in Latin: [hic annus est] bis millesimus nonus.