Re: widget marketing
It's a numbers game really - you want to email as many sites as are potential targets - but no matter what you are going to sound spammy or be ignored by some.
The best approach is to have your email personalized - spend 5 mins on their site and when you write your email (should take no more than 10 mins per email) try to personalize it to how your widget might benefit them (maybe even suggest a spot to put it) - it shows that you aren't just some spam bot.
The part in the middle (explain what the widget is and what it does) can of course be copy / paste - templatized - but I find the best response any time you are emailing a site is adding a personal touch.
Set a realistic goal - 10-20 (this isn't about thousands of links) sites keeping this thing on their site long term would be a great result IMHO
Starting LEC 7 soon but it won't be called LEC 7 - LEC 2012 coming soon!