Blacklisting can be done only for packages that are not yet installed. I thought that blacklisting installed packages would not make any sense, but obviously I was wrong (completely forgot about updating ). I will fix that in some future version.

Package lists are already read directly from apt's cache files on disk, I don't think having yet another cache file would make it any faster. The original cache would have to be parsed for new packages anyway... Maybe some optimizations could be done (the next version will read the cache less often as long as it's stored in memory) but the lists are several megabytes big and reading them from disk will always be limited by cpu power (parsing text) and i/o speed.

It seems that faster application manager won the system&utilities category voting in the coding competition. A big thank you to everyone who voted!

I'll release a new version (mostly bugfixes and small tweaks) once I get back to my computer after the weekend.