With expectations that Twitter will cross the threshold of 500 million accounts as soon as later this month, and with their recent modification to how they will treat requests for censorship concerning tweets, what better time than now to take a look at Twitter activity around the world. A new study from people who know more about Twitter growth and trends than you, Semiocast, show that the hierarchy of countries, at least in terms of accounts and activity, is shifting around a bit.

In the land where parody accounts of celebrities brush shoulders with the insipid accounts of real celebrities literally getting paid to tweet, which is layered on top of millions of actually meaningful accounts, it probably isn’t a surprise to anyone that the United States is home to the most Twitter accounts with nearly 108 million accounts. While fathoming that amount is kind of a headache – seriously, that’s an average of roughly 1 account per 3 people in the United States – it only accounts for 28.1% of all Twitter accounts worldwide. Still, the growth of Twittering Americans doesn’t seem like it’ll slow down anytime since 5.6 million accounts were created in the United States in December 2011 alone.

Brazil and Japan are involved in an interesting contest for 2nd and 3rd place in the Twitterscape. Brazil has actually surpassed Japan in terms of the sheer quantity of user accounts but Japan still exhibits more Twitter activity than Brazil. Between September 2011 and December 2011, the study says, 30% of accounts in Japan posted a message whereas only 25% of accounts in Brazil posted a message. It’s all a matter of which metric you want to weight, but then again, it’s not like there’s a trophy for being #2 Twitter Country (not that there is for 1st place, either). Additionally, Japanese is still the 2nd most used language on Twitter after English.

While the United States might be the girthiest nation when it comes to Twitter accounts, they’re certainly not the most active (you like how that’s a metaphor for a lot of things related to the American lifestyle?). In fact, the distinction of most active Twittering country belongs to the Netherlands. One-third of all accounts located in the Netherlands posted at least one public message between September 1, 2011, and November 30, 2011. Japan and Spain follow in 2nd and 3rd place, respectively, while the U.S. places at 4th in activity. Still, even with the U.S. ranking as the 4th most active country on Twitter, that ranking would surely be lower if not for the sheer heft of accounts existing in the United States.

With so much drama in the Twitter lately, it’s a bit hard to anticipate how these figures will look this time in 2013. By then we’ll have a fuller understanding of how Twitter’s new policy of selectively withholding tweets (if and when they do) has affected users’ activity. Additionally, now that Twitter is expanding languages to be included in their Translation Center, such as Arabic and Farsi, it’ll be curious to see how those changes may affect the landscape of Twitter activity.

Anybody out there got any speculations you wanna bet on? See any changes on the horizon for how different parts of the world might use Twitter? Feel free to share below in the comments.