It's a lot of time and work on the editor's part, for little gain. Finally, there' s the issue of appearance. You've worked hard to bring your product to market, your company has invested many dollars in product development, and the release is its first public 'appearance' of the product. Your company name doesn't stand out, your company logo is non-existent. While the wrapper doesn't have to be fancy, there's a world of perceived difference between a company letterhead and attractive release, compared to the plain text style of e-mail, especially on a PC screen.
Faxes are somewhat better in appearance than e-mail, of course.
With a fax, you can used varied types of text, an attractive layout, and show your logo. You don't have to worry about e-mail mangling, or making more work for the editor who has to decompress a file or print out the release. The immediacy of fax is comparable to e-mail. Both, however, share the photo problem, although with a fax you can at least send helpful line art and even a rough of the photo, which will give the editor an idea of the final photo. It means that you should tailor your vehicle to the type of news you have, and the type of publication you are dealing with.