Important to remember that all the devices in the house (including a Tivo doing Goddess Knows What at all hours) also go through that same router, so if I just sit and do nothing, there might still be too much going on (possibly even without human involvement, altho not very likely).
This matches my sense that if I quit using the computer and just let the Match roll along, it has a better chance of working than if I beaver away uploading more discs and reading news.
In any event, I got through the process again this morning, so the library is now up to just under 7000 songs, of which just under 1200 are uploaded. So in the end, I'm seeing the same 20% upload rate that a lot of other people were getting, with comparable distribution (obscure and/or older stuff is more likely to upload than newer and/or better known stuff).
I'm done with my A-z stuff, and I've done all the not-jewel-box discs and sets that are in donate-able condition. I still have the classical, compilations and operas to do (they are in sets and are done-able, but I don't want to donate them so I am going to keep them).
The end is definitely in sight, and is about 100 discs away. It's funny, because I've always thought of this as a comparatively small music collection, since my husband's always seemed about 10 times the size. The number he comes up with is actually more like 5x, but I'm not entirely certain I believe him. Sometimes he underestimates. In any event, recent googling suggests that my library size isn't anywhere near as small as I had been thinking it was.
ETA: While this review is a little dated at this point and not as detailed as many other reviews, I think it offers the clearest perspective on the benefits and problems of iTunes Match.
I don't fully understand why people are not perceiving iTunes Match as essentially converting your physical CDs into an online license, because that's how I think of it. I assume I'm missing something that other people have and care about a lot.