One of the most popular resources on this website is the Museums on Twitter research, which lists the number of people following different institutions around the world.
One thing that I have been careful to mention when I publish this list is that having more followers isn’t as important as having real engagement with followers.
I have seen a few tools which try and provide useful statistics to show engagement with followers on Twitter, but I haven’t really been convinced, but I think this service from Klout is worth looking at.
Here are some statistics for MoMA (Twitter username @MuseumModernArt) to wet your appetite:

I think these stats on Retweets really show the power of Twitter, with a possible reach of an incredible 193,956 people for the top tweet:

The information below is really interesting, if I understand this correctly it is the link activity of website addresses that MoMA have mentioned in tweets. It’s incredible that with over 50,000 followers, so few people click through!

Overall, MoMA scores very well on Klout (as you’d expect), why not see how your Twitter activity compares.