Here's a smart article about improving your copy from the folks at Marketing Profs.
Nothing revolutionary about the advice therein: Tell a story. Use active verbs instead of forms of the verb "to be." Remove cliches. Use short, Anglo-Saxon words. (This last is one of my own hobbyhorses; it was Winston Churchill, one of the greatest writers and orators of all time, who said, "Short words are best, and the old words when short are best of all"--and please note there's not a two-syllable or Latinate word in that entire quote.)
Seems simple, doesn't it? But nothing, as it turns out, is as hard as simplicity.
Thanks to ksblog for bringing the article to my attention.