This really drives me nuts.

Never create an email message with multiple columns. It's a horrible pain to read. For example, on the screen shot example below you see 3, THREE columns. So I'm supposed to be SOOOO interested in your email that I'm willing to scroll this crazy long thing up and down 3 times just to take it all in? Get real.

1 column is all you get. And be concise. I want to skim over your email looking for good bits to read, and I want it presented to me 1 item at a time. If I find something I like, I'll pause to read or click. When I get a visual overload like this, insta-turn-off. Honestly, no one loves your emails as much as you do. No one is willing to invest the kind of time it takes to sort out this hodge-podge of self-congratulatory happy talk. K.I.S.S. reminder time.

Rotten:

(Click for larger)

Much, much better:

(Click for larger)

A couple additional things to note about this well created email:
1) Approx read-time (nice touch)
2) Table of Contents at the top (this one isn't perfect, but the idea is great)