I first tasted Jack Black one evening, about a year ago, at a bar in Observatory. The only reason I did so was because a friend mentioned that it was brewed locally at a small distillery - hence the word "Premium" in the title. I have to say that it's a great beer - not that I'm a connoisseur or anything, but it's really easy-drinking, which I guess could be a problem. :)
If you read their "Find Us" page you'll discover that this beer is only available at restaurants and stores in Cape Town and the surrounding areas of the Western Cape (or online at Diletto, for delivery anywhere in South Africa). Yet another thing to try when you visit Cape Town. ;-) You can read the story that inspired the name of the beer on the Jack Black website.