Lets try to be little bit less partisan (I know that many people on this forum are GAGA about TikZ/PGF library which is fantastic) and give some more balanced point of view.
There are several classes (I do not mean here LaTeX classes) of presentation tools but classes as in browser based, PDF based, DVI based, Python based etc...
Here is semi-comprehensive list of presentation tools with not such great reviews (for obvious reason a single or even several human beings would have very hard time to be familiar with such plethora of tools).
Now within PDF (LaTeX based of course) class of tools there is almost no contest IMHO.
Powerdot 47 pages user manual (you need to read no more than 10), easily customization well playing with impressive small but active user community. Based on PSTricks its original LaTeX class of presentations (Prosper) which is in works since early nineties.
Beamer 240 pages user manual, most presentation look the same, difficult to customize without at least some knowledge of TikZ, huge user community. In works for much shorter time than PSTricks and based on the proprietary vendor locked data format (PDF) as oppose to a programming language.
I am going for 10 pages manual because I have more important things to do before I deliver that "important" conference talk instead fighting 240 pages of Beamer manual.
Sorry for the slow response guys. I am on a scuba diving trip down at
Florida Keys with my kids so this is the first time this week that I am
in front of the computer. I would like in this edit to summarize my
respond to concerns expressed in the comments.
My original post was meant to present a different point of view but
never intended to be too serious. I will tell you what I really think
about presentation tools.
1- The most first most important thing in any presentation is the content of the presentation.
2- The second most important thing in any presentation is the content of
. . .
1000- The thousandth most important thing in any presentation is the content of the presentation.
Now as of tools my advice to any casual (means you are not paid to use TeX per se) user is to apply principle of the least effort+consistency. Some of the best lectures I have seen in my life have been given with black board and chalk.
As a matter of fact most mathematician of older generation I met have consider using overhead slides, Powerpoint, TeX and similar tools reserved only for very week mathematician who have no new results/content to report.
If you really want to use LaTeX as a presentation tool use least effort and consistency. If you are using TikZ/PGF libraries as graphing tools stick with Beamer and stay away from Powerdot.
If you are familiar with PostScript and use PSTricks then the obvious choice is Powerdot.
If you are using lots of Python to do numerical simulations chose something Python based.
Do not learn new tools just for the sake of learning it.
P.S. As stated on many occasions I am PostScript bias. I am consistent with it.
I use PSTricks, I use Powerdot, all my pictures are in eps format. I can even hack PostSctipt. I like the fact that PostScript is open source for practical purpose. PDF format is vendor locked. Just before this trip I had manually to hack PDF paper from the Annals of Probability in order to print it because of the image stack error with the PostScript version produced with the GhostScript. Error was due to the vendor lock implemented only in Adobe reader. Since I do not use Adobe reader (nor available on OpenBSD) I had manually to fix the PostScript to be able to print PDF document.