I think I can guess what happened here. A trend certainly seems to be starting. The font you were using before upgrading was Adobe's Helvetica Neue, correct? And then you upgraded to Snow Leopard correct?
So, the OS installer because it's been a default for a long time goes and installs it's own version of Helvetica Neue in the System>Library>Fonts folder. Which gives it priority over (if it did not ouright replace your Adobe font) the other font. So, now your system is using Apple's recently installed Helvetica Neue.
The answer is to delete the Helvetica Neue that Apple installed and replace it with your Adobe font. But, beware, unlike with Tiger, Apple implemented an automatic replacement system starting with Leopard. So, the moment you try to replace this font (by deleting it), the OS will automatically replace it with the same copy.
There are a couple of ways around this. Do a Google search for Snow Leopard and Helvetica Neue.
A lot of people seem to be unaware that the installer will always replace it's own versions of fonts back in to the system folders anytime there is an upgrade. This effectively wipes out any other Helvetica's, etc. you may be using with the Apple supplied fonts.
Erik Youngren (Click my name to email me, or the Contact button above.)Composing: Pueblo Publishers
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