2007 Ten Cents - Curved & Straight 7-S / Mint Mark Size

I thought for sure this would have been a topic brought up before but when I did a search I found nothing. If someone could provide a link to a related topic or reply to this subject that would be appreciated.

The RCM's 2007 uncirculated sets have ten cent coins with both a curved and a straight 7, which one is less/more common?
Do all 2007 ten cent coins released for circulation have a straight 7?
Do all 2007 specimen ten cent coins have a curved 7?
Do all 2007 proof ten cent coins have a straight 7?

I seem to remember also hearing something about the mint mark being a different size too. Was this just a different size compared to other years or was there two different size varieties of these mint marks in 2007 alone and can they only be found in the RCM's uncirculated sets?