It's interesting but just like with the Kik ICO I will not touch it. I am wary of these big corporations who suddenly want to do their own ICO 'just because'.
I haven't looked into the telegram ICO yet but from your post I couldn't deduce a value proposition for the token.. What is it actually used for?
And one might question the reasoning behind having a decentralized token (probably ERC20) that can only be used in a centralized institution. Unless they intend to totally decentralize Telegram, which I very much doubt because they'd all be without jobs.