Seems that Win7 phones home now and then. Did some basic poking around and came up with an interesting sollution:
http://jarmund.net/ncsi.html

confirmed working for Win7, as i've tested it myself.
I've been told that it "might" work on Vista as well, so if you wanna test that, it's up to you.

I take no responsibility etc, but it should work just fine.. either way, your computer won't blow up.

And if you have no clue what i'm talking about, read the link.

Moved for obvious reasons.

Gorman: elaborate on what requires explaination?

No it's not.

And why you should be concerned is entirely up to each person. The vast majority doesn't care, while others would like a complimentary tinfoil-hat with the .reg file. It all comes down to the fact that i so far have a bunch of people who don't like advertising to Microsoft that they're online (but rather advertise it to me instead).

They already are

Oh, and just for the record: That change in the registry only affects the "connected with internet access" thingy. Updates and stuff still run as per normal. Basically, it only changes how windows detects internet access, not how it uses it.