Of topic of page traffic transfer, but I've noticed over the years that with home pages case doesn't matter (in typing in a web address), but with with other pages case does matter.
For instance, you can advertise your web address as MyGuestHouse.com on your business card (the caps make it easier for people to read and remember) and whether they enter MyGuestHouse.com or myguesthouse.com in their browser, they'll make it to your site.
But if you have another page, named MyGuestHouse.com/OurBreakfasts.html, they can't get there by typing myguesthouse.com/ourbreakfasts.html because case matters for pages beyond the home page.
I used to blame Bill Gates for stuff like this, but he's turned into such a nice guy, I don't have anybody to blame anymore..
The domain name is not case sensitive, but subsequent pages within the site may be. Example: Apache ( a common web server) is case sensitive out of the box. So a request for mydomain.com/pageone serves up a different page than mydomain.com/PageOne The server treats it as a separate page, so Google treats it as a separate page. So it is not so much a question of, "is Google case sensitive?", but it is more a question of "is your web server case sensitive?".
A web server can be made to be either case tolerant meaning the two requests for the page above would return the same page but keep the caps, or it can be made case insensitive , which means it will automatically force/re-write the page request to be lower case. If your server is case insensitive, when you type in request with some caps in place, you will actually see the caps become lower case.
As Scott mentioned above, a 301 redirect can solve this fairly easily (better with a 301 redirect with mod-rewrite),However that is still a single page fix. It is better to make the web server case insensitive if you can. That is what keeps your PR from being split if someone links to you with caps in the address.
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