The very popular third party social app Seesmic has decided to stop supporting BlackBerry. They wrote a very outspoken note on their blog that on June 30th they will focus development efforts on their “most popular mobile platforms: Android, iOS and Windows Phone 7″. Seesmic didn’t expand on the reason why or give any sort of mobile data, but in Canada BlackBerry has a 42% market share (not sure how many people use apps though). Coming off the disappointing Q1 results last week and now the news of a major app developer leaving is not a good sign, especially when they say WP7 is a more popular mobile platform (can see this in 2012 with Nokia/Micorsoft partnership but not now).
BlackBerry users could always opt for the official Twitter client, or other 3rd party apps like UberSocial and Twit Pro for Twitter.