I love convertible mittens. You get the best of both worlds--the warmth of mittens, the dexterity of gloves--and free fingers for texting and turning doorknobs. I also put a "hood" on the thumb so that when you are in mitten mode you get maximum warmness.
I sort of used Ann Budd's glove template from the Knitter's Handy Book of Patterns, but made lots of mods (obviously.) Now that I've got the basic shape down, I can start playing with finding the perfect texture.
The yarn I used was Knit Picks Stroll in colorway Saphire Heather. It took just barely more than a single ball. I ran out of my first ball just as I was finishing up the hood of the second glove. I had to use maybe 20 yards from the second ball.
I still need to figure out what texture I'm going to use and then who knows when I'll have time to write it up... I guess what I'm trying to say is there is no time horizon for the pattern release yet, but I'm one step closer now.