Research In Motion announced today their Q1 earnings as well as the total amount of BlackBerry PlayBooks shipped. A few analysts estimated the PlayBook to initially ship at about 250,000 units, but it was then upgraded to 450,000 – 500,000. As noted in RIM’s press release, it appears as they have reached their mark by shipping 500,000 units. This is a relatively strong product sale, when compared to other tablets on the market. However, it is estimated has only sold about 250,000 – 300,000 of those shipped.