I usually call Marcie by her name, sometimes I call her Darling Marcie or just Darling. If she is being particularly imperious, I sometimes call her The Queen of all She Surveys in which case she responds by saying “And don’t you forget it.”
She calls me Louie or Ludie and that’s about it. She called me Bunnymuffins for about a week when we first lived together but that didn’t last.
We call each other by our first names.
Never went in for those cutesy nicknames, or even the traditional standbys of “honey” or “love” or whatever. If Pepper mill called me by any of those names, I’d know something was up.
I call him by a play on his first name, usually – this nickname is reserved mainly for my use, so almost no one else calls him this. I also call him honey or hon, or occasionally tweet-heart (but only because when I call him that he whistles like a little bird, which amuses me!). If I call him by his actual first name at home, it’s usually because he’s doing something that bugs me and I want him to stop.
He calls me by my first name. He’s just not a nicknaming person, no matter how much I try.
Well, we also call each other Weirdo or Freak, but that’s when we’re, y’know, being weird. 
We call eachother “babe” for I don’t know what reason.
We also have the bad habit of calling our 1-year-old son “Bubba” instead of his given name (were not even from the south) which is scary if he starts answering to that.
He calls me Pie, or Sweet. I call him the same. Names are for when you have to holler over a distance or distinguish among several people.
Shortened single-syllable first names, or honey/sweetie. Occasionally I’ll call her “sugartits” just for fun (not when the kids are around).
I call her “loon,” and she calls me “goofball.” We also call each other “babe” and “sweetie,” and I’ll often call her “gorgeous.”
We even call each other by name occasionally, when it’s extra-hard to get the other’s attention.
I call him honey, or babe, or love, or sometimes “my love”. Strangely enough, I seldom call him by his name. I don’t know why. A lot of times I call him asshole. That’s usually in fun, though.
He calls me honey or babe, or sometimes my name, or bitch (also in fun, usually.)
When we’re really mad, the name-calling usually either dries up completely, or else escalates to something unpleasant. So bitch and asshole are good. 
He gets “Puppy” or “Boyface.” Sadly, both of his names were made up in response to things I call the cat.
He is not nearly as creative as I am, so I get the usual: Hon, Sweetie, Love.
He calls me Pie, and occasionally will add to it by describing what kind of pie I am (usually double-crust fruit pie, with a lattice top).
I call him Bones, because without him I’d be just a lump of goo.
We both call each other Pup.
I’m Honey Bunny and he’s Pumpkin - from Pulp Fiction. 
Also all the standards - honey, love, sweetie, babe. I call him Tommy Boy sometimes (his name is Tom.)
Me to him: bubs, baby, sweetie, honey, monkey, monkeyman, firstname, diminutive of firstname
Him to me: sweetie, buppi, wifey, boobs, boobilicious…actually there are a whole bunch of names he calls me based around the word “boobs”. I don’t mind.
A few years ago TonyF and I talked about how we’re lazy and fickle like cats, so we started calling each other “kitty”. I asked what color we’d be because I wanted to draw a picture of us in chibi cat form, and he chose black because white isn’t masculine to him. So he became Black Kitty and I became White Kitty. It’s actually quite endearing and amusing to hear our conversations.
“White Kitty?”
“Black Kitty?”
“White Kitty!”
“Black Kitty!”
He also calls me Godzilla if I burp in front of him, Simpsons goat (the one that fell off the mountain and hit a bunch of cliffs on the way down) since I’m clumsy, and 500lb Gorilla (because apparently that means I’m a force that won’t be denied?). And when he feels like being playful, he calls me Chesty McBreasty and Bigteats McGraw.
I call him love, snuggle bug, Tonybear and Squishy Butt.
That’s how we keep the spark alive!
I’m very southern so the pet names get out of control. We RARELY call each other by name except in public.
Him to me: Gorgeous (to which i always scream “SHUT UP”), sugar muffin, baby, dollface, babe
Me to him: Baby, Babe, Sugar Britches, Sammypants, Samurai, Sammalamaa Ding Dong, poopface, Finland, Finbar, Finnyface, Finn, sweetness, there are more its usually whatever comes out of my mouth
Lesse, he wasn’t really my SO, just someone I was involved with when Iwas younger, who called me Anne of a Thousand Nights. Or when I came in Look what the Cat Dragged in. Simce his name was Wilfred, but he went by Wolf Van Broxn I figured that was nick name enough.
But ex ued to call me babe and hun. And I really liked him or he never been able to get away with that.
I call my current Sir, and Master, he calls me cunt and slut…and in less sexual moments, Yes Dear. And I call him My Love.
When we’re being simply and sincerely affectionate, Matt calls me “babe” and I call him “baby.” We have lots of other nicknames for each other, but they’re all jokes and they change frequently – often in response to something we’ve seen/heard. For example, for months after we rented Best In Show he was “Winkie” (much to his dismay), and a few weeks ago we caught part of Gladiator on TV at our favorite bar so right now he’s “Mattimus.”
Babes and bunny. But only if no one else is around.
Babe or hon at home, firstname if at work.
Me: I’ll call you Pumpkin.
Him: No, that’s what my grandma calls me.
Me: Hmmm. How about “Lovemonkey McSexyButt”?
Him: That’s what my grandpa calls me. :eek:
We usually call each other “love” or some form of “sweetheart”: sweetheart, sweetie, sweetie pie, etc. I call him Sleepyface or Sleepypants when he falls asleep on me on MSN.
Generally it’s honey, babe, sweetheart, etc. But since his name’s Phil, sometimes he gets “Phildo my dildo” or “Philly Cheesesteak”. Just for shits’n’giggles.