The five paragraph form itself is a beginner's tool: any good essay will deviate.
However, one nugget to borrow from the five paragraph form is the centrality of the thesis statement. Having a thesis for your talk is _crucial_ IMO. It doesn't have to explicitly stated, and it could be as simple as "I'm going to convince you that $FEATURE is awesome," but you need a focal point. You could restate what I'm saying here as honing your elevator pitch for you talk or in any number of different phrasings, but the idea is the same: a short statement that sums up the absolute core idea of your talk and provides a focus for you and your audience. Anything that doesn't fit your thesis is a good candidate for trimming.
http://presentationzen.blogs.com/presentationzen/2006/01/con...
Ideally, you should never need to look at your slides while giving a talk. Every time you turn away from your audience, you lose a little of their attention.
I appreciate it when a slide is a visual piece with limited text, and the notes are roughly true to the spoken portion (for when slides are distributed after a talk).
You can (and should) repeat key points, but every time you read, you lose your audience. And yes, you can have a little bit of text -- but since most people go too far in the other direction, it's best to aim to eliminate text entirely.
Slides should be simple graphical content to provide signposts and communicate things that otherwise cannot be expressed vocally.
I am happy to provide copies of my slides, but no, I am under no obligation to make them useful without me presenting them. They're my tools, not your reference.
IMO, this expectation has been driven by bad presenters leading people to believe they can get the same content without bothering to show up to the talk. Maybe that's true, but if it is, you should wonder why you're giving the talk at all.
I can understand marketing talks where all you need is you and your words, accompanied with some useless images.
It would be an utter waste of time if a tech talk turned up like that.
You may not like "marketing", but you're giving a talk to sell a vision. Always. Once you win people over, they'll seek out the details for themselves.
You still use the same rhetorical devices and ethos pathos and logos.
Think about your slide and presentation style. For example, I have enormous decks for most of my talks (think like 55 slides for 30 minutes) but I burn through them very quickly, usually less than 20 seconds per slide. I came from film editing before moving to software so I approach my Powerpoints like a movie, it's just my nature. Others have really short decks that are information dense so the emphasis is on the talking part of the talk and the slides just provide a reference in the background. Others forego slides in favor of straight-up demos, which is certainly slick if you can pull it off (high risk, high reward) and need little pictorial illustration.
Use the old 5 paragraph essay rules from high school as a starting point for structuring your talk: tell you're audience what you're about to tell them (thesis, topic, core argument) and how you're going to tell them (outline), then tell them (supporting paragraphs), then tell them at the end again what you told them and how you told them (conclusion, restating your intro).
Humor helps, generally. This isn't supposed to be a standup set so definitely don't go overboard, but it can really help. Particularly if you can tie it in with some empathy for your audience. ("We're gonna do this in Perl. I love writing Perl, you just hold shift and smash the number row for awhile.")
And for heaven's sake don't read your slides.