I'm new at OSM as well (joined a few weeks ago) and can understand Candid's points. But I also agree with njd27: Although I knew about OSM for a while, the decision to join came when I figured out that my neigborhood at OSM is missing a lot of streets and contains a lot of errors. Even the street I live in was named wrong. To start I needed just a few bits of information from the wiki and I could fix some major errors (thanks to practice mode in Potlatch).
I was confronted with information in German that was partly country specific and partly transformation and many information in English, some FAQ, some examples, some use cases, some proposals. And when I look at the map how others did the same, it was even different to what I sometimes read.
Nevertheless, I was able to start. But: OSM is far from usable for occasional users. You have to be willing to dig into the topic and *search* for what you think you need.