Here are the two interior pages from the S-M News Box Score that I started in a previous post. It covers circulation for the last 6 months of 1948 & 1947.
- Lev Gleason Comic Group 
- Archie Comic Group 
- United Feature Comic Group 
- National Comics Group (DC) 
- Harvey Comics Group 
- Fawcett Comics Group 
- Hillman Comic Group 
- The Thrilling Comics Group (Standard/Better) 
- Quality Comic Group 
- Marvel Comic Group 
- American Comic Group (ACG) 
- Famous Funnies-New Heroic Comics 
- The Premium Group of Comics (Novelty) 
Note that Marvel drops from #2 to #10. Demonstrates quite clearly how Goodman liked to glut the market with product.
Another fact to point out is that if you took the Avg Sale Per Issue of the Lev Gleason Comics (703,178), and plugged it into the main list of publications, it would have been #26 on the list. In fact, if you had done that for every one of the Comic Groups, they all would have fit in the top 100. Since each of the Comic Groups consisted of 2 or more comic book titles, had you actually broken the comics down into titles, you can image how overwhelmed the top 100 would have been with comic book titles. Once again, this is without Dell Comics and other publishers whose circulation numbers are not included.
Also note that 4-Most Comics (Premium) and True Comics (Parents Magazine) are already separated out as #52 and #74 on the 1948 ranking.
Now of course, comic books were only at $0.10 cover price where almost every other magazine was at least $0.15 or more. That changes the comparison between them and mags a bit.
If you like these kinds of numbers and comparing sales, a great web site is John Jackson Miller's The Comics Chronicle (http://www.comichron.com). There is massive amount of data and great discussion too.
Update: John Jackson Miller does an interesting comparison of these numbers and today's comic books at his Comics Chronicle here.