Skip McGrath recommends that you put your entire title in caps because it gives it more "pop" when people scan through the search results page.
I've noticed that a lot of people do this.
Personally, I subscribe to the same method. Though when I first started out on eBay I listed everything in lowercase. Though Skip McGrath, swears that using caps is a proven method to increase traffic, I honestly can't tell that it makes much of a difference.
IMO, when people see a product that has an accurate description in the title to what they're looking for, they'll click on it whether it's in capslock or not.
My best tip on creating a winning eBay auction title, is to use the 55 character limit they give you to its fullest extint. Pack as many details about your product on that line as possible. Long titles are oftentimes better than short ones.