As a past secretary/treasaurer.president/etc of many clubs, I can however assure you that your present decision still leaves you with a large amount of manual work to maintain the list of email addresses, which the e-groups thing mostly eliminates. The Yahoo groups thing can also be set up so that only the owner of the list can post, something which has not been mentioned before - thus it can function as a normal sort of post-out newsletter. You can control who can join as well. You can also setup a data base there as well, which can have all your current data - exportable and loadable to any other app you want.

Of course I had ASS-U-MEd :-) that you might want a regular output much more often than just a few times a year, and what you have chosen seems adequate for what you want.

Good luck with your decision. If it does what you want and you are happy, that's all that really matters, in the long run.