Facebook is much much bigger compared to Twitter and even in the growing Google+ for social network. Facebook is regularly updating latest features and I like new look of it.
Facebook and Twitter are other tools so it's hard to compare it, there can be difference in amount of users but also in activity of them. I think people often post something on Twitter.
Even though they seem to be in the same field (social media) their services are quite different. So i wouldn't compare the two. But if you are asking financially, facebook is way bigger than twitter
Facebook is much much Bigger and having huge numbers of accounts, pages, groups, applications, games and many more... so generally Facebook is bigger!
considering figures, facebook is bigger, and considering usage and features, facebook is way better too
No question that Facebook has a bigger impact, but twitter is for a different use really and can be used effectively for those looking to attract a mobile following