May delete to much on uninstall

I suggest yout to change the following code in "userpoints_uninstall()" from

db_query("DELETE FROM {variable} WHERE name like '%userpoints%'");

to

db_query("DELETE FROM {variable} WHERE name like 'userpoints_%'");

Because the first code will delete even variables named "mymodule_userpoints_whatever". Sure, if you uninstall userpoints you may not need those any longer but in development stage one does a lot of enable/disable install/uninstall and it can mess things up.

A module should respect namespaces and only clean up his own settings.

Cheers naden