I bought space for my photos... because I think photos are important to this blog. :-)
I finally found out where to see how much space I am using. But it means that I somehow have a Picasa account that I did not know I had. Clearly it's system generated since the photo albums aren't in any grouping that I would have chosen. And now that I've purchased memory, it's shown on my account page.
It took me 3 1/2 years to fill up 1GB, hopefully it will take that at least that long to fill up 20GB more. :-)