They do appear to have changed somewhat, according to my friend's research. Supereffective reducing berries previously took 3 days to grow to fruition, but it seems like that may have been upped to 5 days. The quickest-growing berries (Oran, Cheri, Pecha, etc.) previously took 16 hours, but it seems they take a full 24 hours now. If you planted an Oran Berry first thing upon entering Dream World, you might not notice this because it would still be ready as soon as you logged in the next day, but if you accessed the Dream World at 7pm and planted at 7:30pm, it seems it isn't ready to harvest if you were to log in again at 7pm the next day, instead reaching maturity at 7:30. The "heals HP but can confuse" berries seem to take 2 days to sprout berries, whereas previously they were 20 hours. The others are most likely different as well, and not the same growth times in GenIV as was originally assumed.
On a slightly different topic, I've begun investigating the actions that supposedly award Dream Points by entering the Dream World, performing an action that supposedly awards Dream Points, and then exiting out and checking my Profile to see how many Dream Points were actually earned. I'm beginning to think the chart from Serebii that we all use isn't completely correct, but I need a few more days worth of data to really be able to say anything conclusively; I don't want to post any conclusions without confirming that they aren't just flukes in my testing.
That being said, does anyone know for sure where Serebii got those values that he posted on his site? Has anyone else tried to confirm them up to now, either from looking at the code or testing it themselves? I'd hate to find out I'm beating a dead horse.
