"...the n900 nokia removed app manager's support to install local .deb files. this means that - unlike on previous tablets - you no longer can just beam a file to the device via bluetooth, or copy it from pc, or just download using the web browser, and tap on it in the file manager to install it. deb files stored locally on the device are not recognized (not associated with app manager) and tapping on them does nothing. from now on, users are expected to install software via repositories only.

it is said to prevent the user from installing incompatible software, or packages missing required dependencies, etc. but this is a poor excuse. the app manager, like on previous tablets, could check for compatibility and missing dependencies of local .deb files and stop installation of incompatible/broken packages, anyway.

more advanced users will still be able to install local packages using x terminal and e.g. dpkg command (unless they block it too), but it should not be like this and linux newbies won't even know about such a possibility..."