same as the storm 2, not the storm.
there's rumors of 2.0 letting you save to the SD card, but apparantly you can do it by rooting your phone too.
but if the android apps are about the same size as blackberry apps, 256mb should be plenty. with the apps i have on my tour (also 256mb) i rarely go below 105mb free and usually hover around 110mb
edit: so i'm reading around that it might even have 512MB, either way, you should be pretty okay with app space...