Few minutes back I saw StumbleUpon down and displaying a HTTP error and after around 5-10 minutes break its back once again. Start Stumbling all over again.

Oops! This is weird? StumbleUpon is down? Did they give any prior notices?

Although nothing is sure about the exact number of users that are using twitter yet the amount of traffic that these sites generate is something that we can study to estimate the popularity of StumbleUpon and Twitter. As per the latest traffic graph from Compete.com, StumbleUpon has something to cherish about. Though Twitter recently registered exponential growth in its traffic due to huge media response yet StumbleUpon.com has higher traffic when compared to www.twitter.com. Yeah! StumbleUpon.com beats www.twitter.com in terms of traffic but when compared to twitter.com then  the story is totally different. One must remember that Twitter URL redirects to a non-www URL which is shown in the image below.

This means if you type www.twitter.com in your browser then www is omitted and twitter.com is loaded. On the other hand StumbleUpon uses www with its domain which means if you type stumbleupon.com into your browser then it will load www.stumbleupon.com as shown in image below.

This simply means that the real URL that Twitter is using for their service is twitter.com while for StumbleUpon it is www.stumbleupon.com. Hence, these two must be compared and other data (the one pointed above) is for SU to boast about itself!