If I was forced to choose only one brand of yarn, Malabrigo would probably be it. It has a lovely texture and the colors are wonderful. I really don't know that much about it beyond really liking it, so I did a little research.
There are a number of new colors, including Ravelry Red, a pastel-ish mix called Kaleidos, and Deja-Vu (my favorite). I'd include a picture of Deja-Vu, but every picture I find looks different from the others. That's the charm of Malabrigo.
Malabrigo makes more than just yummy merino wool. They've got angora, organic cotton, and something called silky merino. Silky merino is half silk, half merino. Atardecer is now at the top of the I want list.