According to this article, Berkshire Hathaway shares might split, making them more accessible to the general public. Shareholders still have to approve the stock split, and the final vote tally might be close. Buffett started giving away his shares to the Bill and Melinda Gates Foundation, so it's unclear if any single person or group controls the outcome of the vote.
I bought my BRK.B shares so I could go to the annual meeting in Omaha, Nebraska. If shareholders approve the split, more people may attend the annual meeting. I'm not sure that's a great idea--when I attended in 2007, the meeting was extremely crowded. At the same time, Buffett is coming along in age, so perhaps he wants to give more people the chance to come see him.