I noticed that. I am still using 8 GB of RAM in my desktop for high end shooters and RPGs. I'm sure I will run into one that needs more soon though.
The storage speed is definitely something to consider... The SSDs are super fast and a few games recommend them to avoid lag times. But they are also much more expensive. Most HDDs in laptops are 5600 RPM which is pretty slow. Most HDDs in desktops are at least 7600 RPMs. It's just another reason why a laptop is not a very good option for gaming unless you can afford a really good one.
When I hit the lottery I would like to put a 2 TB SSD in my desktop! But until then I will use my 10,000 RPM Velociraptor hard drive.