A lot of companies use a loss-leading (pricing below cost) strategy to get their console to sell early in the generation. This generation, the loss-leading strategy was adopted by Sony and Microsoft for the first 12-18 months or so. The Xbox 360 is now at the point where Microsoft is making money on every unit sold and Sony may be getting close to that point as well.
Nintendo, on the other hand, priced the Wii above cost at the start, and has been making a profit on every unit sold since launch.
Games are, indeed, the biggest source of profit for these companies, but they aren't necessarily the only source.
Edit: Oh, and there are charts for video game sales on this site, they just aren't displayed as prominently. ;)
"The worst part about these reviews is they are [subjective]--and their scores often depend on how drunk you got the media at a Street Fighter event." — Mona Hamilton, Capcom Senior VP of Marketing
*Image indefinitely borrowed from BrainBoxLtd without his consent.
