Question about Memory for 10" Models

I was planning on purchasing a 8.9" Acer Aspire One and even bought the memory from Newegg, a 1GB stick. I figured I'd use that to expand the Aspire One to 1.5GB.
Shortly after I saw that the 10" models were coming out so held off on my purchase. I was hoping the same memory would work on the 10" Aspire One and I think it will.
From what I'm reading the 10" Aspire One's will be expandable to 2GB instead of 1.5GB. Also, as part of this it appears that unlike the 8.9" (where there was 512MB internal, 512MB in the slot) it has just 1GB in the slot and to upgrade to 2GB I'd remove this 1GB and put a 2GB stick in. Is this correct?
What type of 2GB memory would be needed? Im ready to sell the memory I purchased on eBay and look for 2GB of memory on Newegg.
I see the Aspire One's are up for preorder on both Amazon and J and R. I think they are out in late Feb. and honestly I can't wait!

 

If I am not mistaken the new AAO should support DDR2-667, however it is still compatible with DDR2-533.