Well, if you're gonna argue 250,000 isn't enough, the least you can do is point to what you think is a good number.
to me, this is no different to saying there are 6.5billion people in the world, but only 75million bought a Wii, therefore the wii fails cuz you know...the world has a large install base so everyone should be buying a Wii.
Everyone knows that the PS3 caters to a VERY diverse market who like completely different things from one person to the next, why people are always surprised when something doesn't do a zillion in 10mins is beyond me.
You assume that every ps3 owner is online, uses Home and rushes to every new space released on Home on day one, I for one I'm an avid user of Home but even I didn't use it till about a week after the E3 space was released.
I maintain, anything attracting 1/4 million of people in a few days is an achievement regardless of how many people the "potential" it has to reach. This is why I say 250,000 is an achievement.