Without booting it up and looking, I think it has 2 gb. It is a Sony with just about everything. Even GPS. And that's the one thing I'm having trouble getting to reliably work since the 7 upgrade. I found a forum for, among other small computing devices, these netbooks, even broken down by brand. Pocketables.net. Great resource. It was there that I learned of the bad mix of Vista and the Atom processor.
But let's face it, Vista was just a bad O/S. I had 3 machines with Vista, and truth be told, I never experienced what many have, the "blue screen of death"(a phrase BTW, which came about because of Vista). Just before Vista graced my front door, I had heard about driver issues, so I took steps to get the right drivers for my add-ons and never had an issue. The desktop fried a motherboard from a power supply issue. It was replaced under warranty, and the replacement had XP!
I don't know if this is true, but the story I heard was that there was a race between 2 teams at MS, started about the same time, for what we now know as Vista and 7. Obviously Vista won, but it would seem at a cost. Makes sense to me.