On the whole it is very bad, so when you see something interesting, relevant, well art-directed and targeted, it instantly stands out.
The Christmas mailing from Tesco is a perfect example of how direct e-mail should work. It instantly highlights benefit. It is precise and clear and you can follow a route to the information you are most interested in.
The other trick this work pulls off is providing lots of product hits without looking cluttered. It also manages to fit with Tesco's other brand communication.
The lead proposition is also spot on. Anything that can appear to save you money on drinks at Christmas and make seasonal shopping easier has to be good news. More direct e-mails should be created to this standard.