When it comes to press release writing (and many other forms of writing for that matter), brevity is not only allowed, it is encouraged and rewarded. Editors and reporters are always busy, so you need to keep your press releases as short and to the point as possible. If they need more information, they'll ask for it.
==> Mastering the Fine Art of Writing with Brevity by Mickie Kennedy, founder of eReleases
Of course, concise writing is an art. How can you become a master of this art? Here are some simple pointers.
==> Cut (buzz) words -
Well, duh. If you want to write more concisely, you need to eliminate words. I'm a genius, right? But seriously, press releases are the worst of them all when it comes to using superfluous words. Ditch the unnecessary buzzwords, industry jargon, and superlatives. Make sure every word you use is necessary to support your story, and make sure you aren't using any phrases that are causing your writing to be longer than it needs to be (e.g. using "are going to" when "will" suffices).
==> Don't try to make something sound more important than it is -
The late George Carlin used to have a comedy bit where he said that people add words when they want things to sound more important than they really are. He said, "Weather men on television talk about 'shower activity' [because it] sounds more important than 'showers'."
Like Carlin, this annoys me too. The other day, I heard someone on TV talking about the "family unit" when they could have just said "family." Don't add words to try to make something sound important. Just tell your story!
==> Write like you talk -
That doesn't mean you should write using slang. What I mean is to write in plain English. Try to capture a conversational tone. Imagine you were telling a friend about your story, and write your press release accordingly.
==> You don't need to use longer words to sound smart -
Don't say "utilize" when you can just say "use." Don't say "facilitate" when you can just say "help." Choose simple words so you can keep your press release easy to understand.