I've gathered ca. 1000 emails so far on my new programming screencasts website. The call-to-action was "episode alerts", FYI.
For a while, I emailed out each episode, but I noticed that each email caused maybe 1% of the list to unsubscribe, which is painful considering how much effort goes into winning a subscriber.
I've since reduced the frequency of mails to every 3 or so episodes (i.e. every 3 weeks). But I can't tell whether this is good idea or not.
On the one hand, mailing every episode means my content gets more eyeballs (and more chance of some virality via social media shares). On the other hand, if I hold back on using the list, then I'll have a larger list to one-day pitch any eventual paid offerings I launch.
What would you do in my situation?