You can only have your content coming out of one domain; otherwise you're going to fall into the supplemental index for duplicate content. Which means you'll come up for searches where there's nothing in the main index that's relevant to whatever the user is searching for, and that it might be six months before GoogleBot returns to evaluate your page again.
You can add as many domains as you'd like to catch misspellings or whatever, but you really need to redirect them - with 301s - back to your main address.
OK I've been thinking about this too, because I've registered whymhost.co.uk as well as whymwebhosting.co.uk and I really don't want to get done for duplicate content. Thanks for the info
True, but there are so many mispellings with the relatively unknown word, "whym", that my customers could drive themselves mad trying to get back to my site
If it's because someone might type whyme.com or whim.com, then it makes sense to buy and redirect them. If it's Whymberly.info then it's probably not worth your $1.
