Are eastern European countries included in the schengen visa?

Some Eastern European countries are in Schegen, some aren't.

The full list of the 26 current (as of 2012) members of the Schengen area is:

Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden and Switzerland.

Bulgaria and Romania are due to join Schengen in 2013.