How can you tell if you are host?

For a Public Match.

your shotgun shells pop out of your gun immediately after you pull RT instead of arrving at christmas

fire a shotty at the wall

I read somewhere that the host can give "powers" to the other players on his team. So will it still matter?

lol true

You will know because you'll have the power of 1000 suns!

When you lead the game in kills

You will know basically when your owning everyone with the shotgun.

theres no other way of knowing =\ besides shotgun?

I know I'm host when everyone took a long time (generally 10+ seconds) initially connecting to host, it takes 30 seconds to begin the countdown to the match, everyone with a mic on my team is complaining about lag or asking if anyone else is experiencing it, everyone on the other team is hardly moving, I can run up to opposing team members and shotgun them without them fighting back, I run through their bullets without getting hurt, and when after the match everyone on the other team tells me they're reporting me for cheating. :)