But seriously, I leave feedback as soon as I receive an item and I always send a follow-up email stating that I received the item and left them feedback...and then I forget about it.
As a seller (which I've only done a few times) I always leave feedback as soon as payment is received and I ship the item...I don't wait for them to receive it or leave feedback. Afterall, they've already done their part.
Most sellers seem to leave feedback either when they ship, once the buyer leaves feedback, or they do it 'in bulk' periodically. In fact, I just had positive feedback left by a seller from an auction I won 2 months ago!
The ones who don't leave feedback? Well, I just don't worry about them. The last thing I want to do is harass anybody.
You can always look at their feedback page and see what kind of feedback they leave for others...and you can compare the number of feedbacks they've received to the number they've left.
If it is really important to you...don't bid on auctions where sellers don't leave feedback. And, if you feel so inclined, drop them a note and explain why you're not placing a bid. Maybe they'll get a clue.
WarriorNun
"If you can't be a good example, then you'll just have to be a horrible warning"