RealTimeWWII, about as reliable as wikipedia.
...actually there have been comparative studies that show Wikipedia has become more accurate than traditional encyclopedias like Encarta. In addition, if compared to the others, Wikipedia shows more depth of knowledge about shared subjects. Compare a 500 word entry on Encarta to the basically unlimited word count of a Wikipedia entry (Abraham Lincoln for example).
The whole idea that Wikipedia isn't "academic" stems from a variety of reasons that date back to the sites infancy. Since then they've had to legally beef up the regulation of the site and the requirements for a post's publication.
I find it's a good place for general background information and, since you now have to provide references and citations (some with links to scholarly articles, books, etc), a great and handy springboard to broader studies.
Wikipedia is also becoming the go-to place where sites such as about.com go to simply copy and paste the info to their own site.
Some things on Wikipedia can certainly be disputed, but to say Wikipedia isn't "reliable" is somewhat inaccurate (no pun intended).