I am considering residing my house with cement board siding. My main question is how does one handle protrusions such as electrical and gas meters. Do you somehow remove these items or do you cut the siding to fit around them? I want a professional appearance.

Cut carefully to fit and caulk around them

For Gas, Don't Touch Them, If There Is A Gas Line In The Way We Usually Will Make A Joint At The Line That Runs Into The House , As Far As Outlets Go, You Need To Get You A Different Box Most Likely That Has A Bigger Cover On The Outside,
Just Watch Your Measurements, Maybe Alow 1/16 Bigger That What You Need Up And Down.
Once The Sideing Is On You Can Put Your Cover Back On,

You Didn't Ask About Cutting It, But You Need A Mason Blade, Id Adivse To Get A Diamond Blade, Just Like A Tile Cutting Blade But It Has Ridges, And Don't Be Cheap Here Either, If Your Doing You House Get A Good Blade Otherwise You'll Wear The Cheaper Ones Out Quick With This Type Siding, It Is Also Very Dusty, Get A Mask, And Safety Glasses, (not As Much For Bigger Pieces Hitting You , But For All The Dust)
This Stuff I Think Comes In 12' And 16' 2 Saw Bucks Really Don't Work Well Enough Because Of The Flex It Has, Id Get An Extra Buck

Lastly, Nailing It Up We Use 8penny Spiral(get Spiral Lol) Galvanized Nails
Hope That Helps