The maximum allowed is 853 passengers and 20 crew members. That's what the a380 is certified to carry in Europe and N America.
Strategically the niche market (600-800 passenger market) does not support 2 megaliners. Boeing has decided to improve apon the 747 design instead to maximize that platforms capacity. Boeing stopped development of a similiar megaliner project back in the 1990's.
It remains to be seen whether Airbus can make the a380 a profitable business. The development costs are $11 billion, production has been seriously delayed numerous times. And ... the plane weighs a lot heavier than advertised, which affects fuel economy significantly. So ... with these problems; it remains to be seen whether the a380 is (in investment terms) a White Knight (that could save the company) or a Poison Pill (that could destroy the company).
We'll see in the coming years, however early indications are that Airbus is in financial trouble by investing so heavily in the a380 project. Its a huge gamble ... it may still payoff.
http://www.bth.se/fou/cuppsats.nsf/04c233cb0d90bad0c1256cec00325988/465e52e638b57294c1257354006311eb!OpenDocument
http://news.bbc.co.uk/2/hi/business/6916982.stm