Facebook has increased the size limit on photo albums from 60 to 200, thanks to a new storage system dubbed Haystack. The jump in storage capacity was a necessity for many users, as Facebook is the largest photo-sharing site on the Web.

More than 15 billion photos have been uploaded to Facebook, with an average of  220 million new pictures showing up each week. Facebook creates 4 images for every one added, and those huge numbers required a more robust support system. The new infrastructure reduces bottlenecking brought on by the enormous amount of metadata information needed. This translates into quicker access to photos by users.

Facebook said sharing has increased since the limits were gradually increased over recent months. The additional space could also draw in more users who may have been reluctant to make the move to Facebook from other sites based on Facebook’s limited album numbers. These users generally send in a lot of secondary traffic as they promote their own photos and steer friends and relatives to their online albums.

Facebook is obviously recognizing and catering to how the site is being used, and this move should enable Facebook to keep more and more traffic from the traditional photo-hosting sites.