I suggest if you are serious about your business/website i think you should register maximum possible extensions.

I had read a blogpost where in a very popular blogger had a .org and a *.blogspot.com to his name and someone to take advantage registered a .com and then used a script to scarp content from the original blogger's site and earn money out of it. When the original blogger found out about it it was a lot of headache for him as the person who did the stealing work was quite adamant and the original blogger had to file a case under the DMCA!!

So, although this is an extreme case this can happen to you and hence i believe it is very essential to get as much extensions as you can and have a 302/301 redirect.

Thanks!!

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