Ruble symbol?

[Jean-François Colson]

Hello

At http://store.artlebedev.com/electronics/optimus-popularis/ I see a 
price in rubles, 31,500 р, where the currency is written р (Cyrillic r).
But that р is displayed as a capital Р (Cyrillic R) with stroke.
I’ve never been in Russia. That’s why I have a few questions:
Is that symbol is in everyday use?
Is it common?
Is it new?
Why doesn’t Unicode support it yet?
Thanks for the answers.

JF