The problem is we already know what's coming in 3.5 as a whole. What you said only works if the original patch notes were equally a surprise to the entire population, but we as a community already know what happened to Live from 3.5 on to 5.0. The hoarding has already begun for anyone with half a brain that saw the downward spiral Live went through once this patch dropped. Knowing what's coming HERE has the following scenarios and resulting behaviors:
A) They can change a small amount of stuff for the better = this tells us to continue hoarding based on some of the expectations from Live coming to fruition here, and could even lead to the reaction seen in option C
B) They can change most, if not all, of the stuff for the better = this tells us we can ease back on the hoarding and harbinger-ing because things here will end up easier than what happened on Live
C) Nothing we want changes = this tell us whether or not we should even bother donating anymore because if they're unable to change anything and we know there's a countdown to doomsday already, players are less likely to stick around knowing the end is near.
So the fact that they aren't telling us anything is troublesome because, in 2 of these scenarios where stuff will be changed for the better, all we would be doing is the same exact thing we did on Live (hoarding materials, which is already happening). The 3rd scenario is the worst case for us AND them, because it would guarantee those that know what's coming in 3.5 will refuse to stick around to repeat participating in a failure and people would stop donating to the server early. So we SHOULD know what's coming. It's worrisome that we don't.