One point I'd add that seems minor but isn't, in cases such as this where the school has no structured policy in place you would first want to make sure that the school administration accurately ID's anaphylactic allergies therefore ensuring all forthcoming policies acknowledge and inherently refer to that definition. Otherwise you'll get a big hot mess of co-opted "allergy" definitions which are most likely neither medical or legal disabilities and guess who loses out. Yes, the kid with documented LTFA.

No...If no nurse, have the teacher or preschool director do it.

No, no and no.  It sounds nice in theory but just no.  We can all but guarantee it will come back to bite you in the butt.

I am guessing there is no nurse? 

I would just have the director say we have a list for health reasons (doesn't have to say allergies) and leave it at that.

I know its tempting and you would hope to appeal to your fellow parents, but unfortunately not everyone will be supportive.  Also I think overall it weakens your position because it can seem optional to comply etc.  best education, rules etc come from authority at your school.

Just my $.02. 

I absolutely would not get up and speak in front of the parents about my child's allergy or even food allergies, in general.  While to date your experience has been positive with other parents, it will not remain that way.  I speak from experience.  In hindsight, I wish that I had been more circumspect about sharing that information. 

It only takes one parent listening to your presentation who disagrees with you to make things difficult going forward. 

Remember what you've agreed to do is share information about a medical condition your child has with people you do not know.  Do you normally do that for other medical conditions? 

Well, I would probably ask the nurse to do that. 
If "you" do it, then all the allergy rules will be seen as "your" rules, not the school's rules.  Could you meet with the nurse and make a plan for what needs covered and ask her to do it? 
Just my .02

My child just started preschool. The classroom will be safe foods only (I vet what they buy & provide approved lists of safe foods).
The teacher wondered if I would like to talk with the parents at a parent day in a few weeks. Since he is is being so accomodating I agreed. What to say? Some other kids have allergies, although none have as extensive or required epis (yet). It's not a new topic.  I  believe I am introducing my childs allergies.  In my experience the more folks that know the more will work to keep the setting safe. Other kids can be great advocates given the right amount of information (of course we see bullying too).

So, how would you handle this? I don't want my child  to be only identified as "the kid with all of the allergies" but I do want folks to be aware.  I thought of relating a little story about her (non- allergy related) and then stating her allergies and thanking them for being mindful and accomodating. Is there anything you wish you could tell parents given the opportunity?