The number of changes Knuth might make this year to the core TeX engine code will be, I suspect, somewhere between a handful and vanishingly small. Regardless, any such changes should trivially be incorporated into future builds of pdftex, XeTeX, etc. using the usual automated Web2C/".ch" file compilation processes. There are, of course, a whole slew of large- to very large-scale changes that TeX's code could benefit from, but DEK isn't in that business and he has other more important work to do these days. Plus were I in his shoes, I'd be worried about any changes large enough to create a new pagination of the typeset ("literate") version of the code/book.
Were I betting man, I would wager $1.00 (hex) from the Bank of Sans Serif that at least one minor typo (so to speak) will be fixed in the code's English exposition this year. But I'm not because I don't want to risk losing the check I received for finding it.
version 2.0.something.something
toa new different thing
? – Mario S. E. May 30 '13 at 14:24