re 2 and 3: Definitely have a very big presentation screen, but if you let avatars get reasonably close, everyone should be fine – even the folks who don’t know how to zoom in SL, given the small amount of text (and clear font size) recommended for slides

re: 4, don’t give a presentation to a large group over the VOIP system, rather stream it in over the audio/music channel. Or stream in video. The benefit of using this method is you can stream to multiple venues and scale the audience.

Have a helper(s) in the audience so that you, as presenter, don’t have to deal with confused people wonder how to turn on the sound.

5. definitely use headsets if you are using VOIP for a conversation after the presentation

6. yes, test!

7. yes, a common mistake in SL is making giant structures and amphitheaters that might look grand, but end up being depressingly empty since they can only fit 50 in one place. You are better off in a smaller, more intimate space.

8. yes, ask people to remove unnecessary attachments and turn off scripts.

Plus:
- reiterate that your life will be easier if you have a helper to work with audience, letting you focus on presentation

- you can prevent griefing occurances by changing the land settings, so that visitors cannot “rez” objects, or run scripts. You might also want to make sure that someone is there who can boot an unwanted visitor from the land plot.

- remember that you aren’t limited to a 2D screen – you can bring 3D objects and interactivity to your presentation if fitting

- come right out and welcome a “back channel” to take place in the text chat while you are speaking. It is one of the best things about attending a presentation in SL — participants can talk with the audience (comments, questions, etc) while the speaker is talking without interrupting. On that note, your helper can try to pull out and flag relevant things being said in the back channel.

There’s a lot more, but there’s a few notes for you riffing off of your list.