I'm running MacOS X 10.6.2 and contextual substitution works correctly in Text Edit (1.6) but not in Pages (4.0.3). I seem to recall that Text Edit started doing it correctly with the release of 10.6. Perhaps Pages has not gotten the fix yet. Which versions of OS and apps are you using?

My stuff's a little older:
OSX 10.5.8
TextEdit 1.5
Pages 2.0.2

Hmm. I suppose the workaround would be to generate separate font files for the different swash forms, for users without access to properly working OpenType setups. But then I wonder how many users there are who would go to the trouble of understanding, installing, and using separate fonts to get a swash, who also wouldn't have such access...

Actually, Mark, I see that you do just that (offering alternate fonts for the OpenType-impaired), so maybe you'd be just the person to ask: do those sell?

I think no one using TextEdit would care about contextual substitutions (but maybe I am mistaken). If it works in InDesign (and Illustrator), that would be good enough for me.

The fact that it works in Text Edit (in 10.6) means there is OS support and that Pages and other Cocoa apps should be able to support contextual subs correctly--just not many of them do yet.

But, yeah, I think most people interested in using OT fonts with advanced layout features will tend to use them with Adobe CS or Quark 7 or later. It's very frustrating that support for stuff like that beyond pro graphics apps is still so sketchy.

do those sell?

I don't sell them separately. I include them with the full OT version (no extra charge).