Care Of Boots With Slightly Napped Leather?

[Jon in GA]

I have a pair of Wolverine Wellington-type boots, in some sort of slightly-napped leather (nubuck, I think, though I'm not 100% sure).

One of the things I like about them is that due to the nap, etc., they don't show scuffs and scratches easlily. They're getting a little dingy looking, though, and I need to do something to restore the appearance some.

What do I do with this? I experimented once on the heel with a little mink oil, and got the result I expected - it slicked everything down, making it look almost like full-grain leather. (Which is interestingly what has happened on the heels, where the hems of my pants rub when I walk.) What sort of conditioner works on this stuff - and do I brush it?

Thanks!