Do you think this would mean we'll get those updates available online? If they incorporate them into new prints of the PHB, would you re-buy the PHB to have it up-to-date (or how much updated does it have to be for you to buy it again)? If the PHB reprints included not only updates, but also some additional material (like the 3.5 core books had) every year, would you be more interested?
If the game's flawed enough to justify a major revision a year later, chances are I won't be playing it in the meantime, so I'd have little interest in investing in a new version.
If the flaws are minor, requiring only minimal revision, then the updated rulebook won't provide sufficient new material to be worth buying again.
That's like me getting an OS for my computer, then having to rebuy it every year to get updates.