Yes, the numbers you posted are true, but there's something else to consider. The cap is set relative to total league revenue. Of course, not all teams are created equal, so the NY Giants bring in more revenue that the Detroit Lions. Just because the cap is $123 million, doesn't mean that all teams can afford to spend up to that limit. Can the Packers? I'm not sure. You might want to see if you can find team revenue numbers for the past five years in order to determine what would be a reasonable spending limit for 2009. That may be difficult to impossible to find though.
EDIT: Typing "packers revenue" into Google brings up quite a few articles over the past 5-6 years. I won't post them all here, but they show that the Packers are consistently in the top half of the league in terms of revenue and had jumped all the way to #7 as recently as 2006. Now that's a very quick and dirty analysis of the Packers financial constraints, or lack there of, but it would suggest that we don't necessarily
have to keep our hands on the purse strings.