Here is the link to this article...
http://www.autoweek.com/article.cms?articleId=100378

Here is the full Subaru quote...

For instance, even though Subaru pops for a one-year SCCA membership for every interested WRX buyer, and in its marketing materials appears to encourage owners to enter their cars in autocross events, the company says autocrossing is racing and racing can void warranty coverage. The WRX/SCCA application form says the SCCA"looks forward to helping you fully experience the benefits of owning this car."But the form also includes a disclaimer that Subaru’s warranty excludes "damage or failure resulting from participation in competition or racing events." "If the damage looks to be racing related, you’re not going to be covered," says Subaru spokeswoman Larkin Hill. "We don’t want to punish the person who goes out once in a while and autocrosses—and that shouldn’t cause any problems with the car anyway. However, autocross is considered competition and the warranty does not cover abusive driving or competition. If you’re out there racing every weekend, you can’t expect us to fund it." (end)

I think it speaks for itself, Its not like they are hiding the fact that racing may void your warranty. And if you feel you have a proper claim, you might quote the Subaru representative above to your benefit. As this statement was made in a well respected magazine. Now Mitsubishi... well that is another issue.