I picked up on this thread after I was unable to install a paint program called faint from the maemo garage and got the text file instead of the expected application manger install cycle.

I have, however, recently installed several apps from the .deb files, including canoe (just now) and omwether applet (earlier this am). Given that I was able to install faint pre-new firmware, my guess was that it was a compatibility issue (faint is in alpha, so it didn't seem unusual).