When it comes to viewing photos, we think bigger is better. The Facebook Team begun increasing the maximum size for photos on Facebook by almost 20 percent to 720 pixels to give you higher quality photos and make viewing them more enjoyable.

You'll start to notice the larger size as you upload new photos to Facebook or browse new photo albums from your friends. Older photos will remain in the previous maximum size of 604 pixels.

Old photo size (left) compared to the new size. (Note that actual photos are larger; this shows scale only.)

All uploads on Facebook.com will support the new photo size, but uploads made from some external applications may continue to use the previous size. The larger photo size is launching gradually over the next few days, so you may not notice a difference right away

I personally consider this a great update; some people were complaining about Facebook made photos too small, and now they can upload it using almost its original size. Thanks Facebook!