X-10 Status Module

I have been automating my home since before the 2-way status modules came out. I have yet to buy a status reporting module but I'm thinking of upgrading the lamp modules. In reading the sales stuff on them I get that they report and Off to On condition.

Do they report when the load goes to 0 (light gets turned off) an Off condition or is it still reporting an on condition?
Im not sure, but Im guessing that is exactly what they do... send an OFF command that is.

Anyone know for sure?

One other thing I've read is that too many 2-way switches can flood the powerlines. Makes sense, I guess, but how many is too many?
I guess the question is confusing, but as far as I know, it will report an OFF whenever the light has been turned off, either by hand or remote.
They report an off condition when turned off AND they also report an off condition when polled by another device... such as a 6 or 8 button keypad.

This is nice as the LED on the keypad indicates the status (led on if light is on or led off if light is off).

Also usefull when programming... check status on a particular light and then do some action depending on the condition.