the reason for removing the feature, as I see it , is that when people installed random stuff that exploded their 770, there were people on itt to help those few. However the N900 have a much wider user scope, hence the problems is much greater. Removing this feature actually discourages people to install applications from dubious sources, but does not prevent it.

A nice shellscript and browser add-on to run it, would make a click-to-install debs straight off the interwebs feature available.