The 3-disc set will include the director's commentary, a panel discussion on dyslexia, deleted scenes, the making of, the background score, and two collectible postcards. The contents sound very similar to the T-Series release in India (I hope it comes packaged in standard DVD cases, unlike the T-Series version), except that this one has also been dubbed in English. This, following the International Dyslexia Association conference in Seattle earlier this year. From Aamir Khan's related blog post:
One of the interesting points which came out of the Q&A was the request from the audience to dub the film into English when re-released here. They felt, and rightly so, that they wanted their children to see the film and were afraid that the smaller kids will not be able to read the subtitles. So I’m going to look into that. At the very least the DVD release here can incorporate a dubbed version as well.
I really like this idea of dubbing the film for children who are unlikely to be able to follow along effectively with subtitles (I wonder how they've treated the songs). He's never focused much on the awards circuit. It's been for the better, and it shows here. In other Aamir goings on, his commercials for the Incredible India Atithi Devo Bhavah (Guest is God) campaign have been airing for a while. If, as a tourist, you have felt insecure because of the treatment extended by some, I'm sure you can appreciate this.
The words at the end: "Visitors to this country are our guests. Protect them, and earn respect for the nation." Aamir's performance is a remake of sorts of a critical scene in Lagaan (2001), involving the debate on whether Kachra the untouchable should be included in the team. There's also this commercial that addresses preservation (or lack thereof) of historic monuments. The song contained within is the fantastic Sau Saal Pehle by Mohammad Rafi and Lata Mangeshkar, from Jab Pyaar Kisi Se Hota Hai (1961), with lyrics by Hasrat Jaipuri and music by Shankar-Jaikishan.
There's plenty more at the campaign website, the Incredible India website, and their YouTube channel, which also includes this beautiful rendition of Saare Jahaan Se Achcha by Shaan and Shreya Ghosal (the lyrics are by freedom fighter and philosopher-poet, Muhammad Iqbal; complete lyrics and translation available at this Wikipedia entry).