This is not meant as a sentimental entry. It's about marketing and communicating a message to your potential users. Too often I find myself at a website of an Open Source project and ask myself. "where am I now? what the -beep- is this? and what can I do with it?"
As personal example I take kmess.org as example. We tried really hard to fix this. The site is a lot of content nowadays, but we think there is a lot of room for improvement. While discussing this we Valerio came up with the following blog entry:
Why Ubuntu 8.04 needs better marketing
That article shows the big difference between a summary of technical details and something that appeals. Their revised announcement makes me all of a sudden excited about downloading Ubuntu 8.04. Less technical wording, clearly written sentenses and focus on what advantages does it has for me. Worth reading, this article is written really well!
In the comments there is also a nice observation:
The key however is to, like Apple, make a directly emotional appeal. Even Intel claims to be trying to take this route, inspired by Apple (successfully? Maybe).
Take a look at Apple’s OS X page: http://www.apple.com/macosx/.
The bold heading is very dominant. And it doesn’t really contain too much logic… again, it is an emotional appeal.
I really like Apple's site. It makes me enthusiastic about their products, and while browsing it just goes on. Yet I can also find a lot of technical details there. I couldn't describe why, but now I'm starting to understand the key aspect here: emotions.
Another example: Last week I was on a holiday/journey, and tried to explain a bit Aikido to the guy next to me. It's the martial art I practice and love. In the years I developed a few short phrases to explain it but somehow my description didn't get though at all. 
Fortunately I got a little advise whispered in my other ear: "you are too technical". Dang! I'm currently inspired by "feeling first, mind later" theories and this is another eye opener for me. By using more vague descriptions adjusted to the receiver (communicating a feeling/emotion) the other guy managed to get it a lot better. Whoa. Using less strict descriptions actually makes people grasp something better?
This incident among others makes me realize a lot of people are probably wired this way (call them alpha's if you wish). As technicians we love to communicate details, and the receiver can reconstruct the same image in their mind. Most people are not like that, or can't manage to be so. I didn't expect this gap could be so big. I noticed how this guy next to me responds much better while communicating an emotion, feeling or vague description (which you can technically put down as inaccurate, misleading, etc..). It has a strong effect, as the message is received in a more powerful way.
Meanwhile I'm starting to get an itch to do something with this conclusion within the KMess website too.
If a lot of people are wired this way, shouldn't our websites reflect that?
I'd like to call it "communicating emotions". 
<shameless-plug>We're looking for more ways to improve the KMess website. If you have suggestions, don't wait any longer and post them!</shameless-plug>