no it doesn't. places like Program files, and all those kinds of places would still be protected by UAC (unless it's turned off, or on XP, in which case it's moot anyway).
That mentality is really a case of PEBCAK, not the programs. This is why i would go for letting the user specify where to look for the plugins... not just auto-dumping them in Documents.
I ALWAYS separate my Windows/Programs installation onto a C: partition, and put as much as possible of all my data, documents, program settings and such all on a separate partition, all nicely, neatly organized how i want them, including repointing all the shell folders (Documents, Pictures, Music, etc.) to my own folders. This way when i transfer to a new machine, i just copy my one partition, and I'm done.
So i would LOVE for the ability to specify where they are, so i can keep them organized according to my personal filing system.