THE LATEST scientific evidence suggests that there may be some 50 trillion galaxies in the 'known' universe.  (However. this estimation is based purely on the current level of technology) 
 

This is the largest scale picture ever taken. Each of the 9325 points is a Galaxy like ours. Galaxies clump together in 'superclusters' around great voids which can be 150 million light years across.

 

Below:  A handfull of Galaxies each containing 'billions' of stars like our sun

 

Is The Universe Open Or Closed? An open universe expands forever because it does not contain enough matter (also called mass density). Space is said to be negatively curved, as first described by Einstein in his law of general relativity. A closed universe eventually stops expanding and then contracts, to ultimately collapse into a black hole.

In such a universe space is described as positively curved -- the universe folds back in on itself and space is unbounded but finite.  The Hubbel Telescope is currently doing Deep Field research to answer this question.