I'm not sure where you got that from, but from memory some people are using 8 and 16GB cards. I'm using a 4GB micro SDHC card at the moment and I doubt I'll ever fill it. I've got heaps of books and HTML files on mine and still have way more space than I'll ever need.
When asking about the 32, I think you've gotten your units mixed up. In your second sentence you've said 4MB of RAM expandable to 32GB, that should read 32MB, I think.