Tips for Meta Description writing...

Your meta description is an ad for your page.

It should follow the same rules as a headline...

If your page is an information resource than
your meta description should describe what
the visitor will get when he clicks through
to your page.

In the major search engines your description
will be competing with 9 other ads (descriptions),
so make the benefit of clicking through to your
page apparent. Some other adjectives that
come to mind when writing ad copy are...

Succinct, Pithy, Visceral etc...

Include a hook that will entice the reader
to click through to your page by...

• Creating curiosity
• Promising answers to a question or solutions to a problem
• Including a key benefit

You'll also want to read the following...

The BIG Website Profit Making Secret

One last tip...

Test your descriptions like any other piece of
ad copy. See if you can improve click through
rates by writing a description with more impact.

While changing your meta description isn't really
a feasible option, due to the slow update schedule
of the search engines. You can use PPC programs,
like adwords, to test the response rate of your
descriptions.

Test until you find a benefit or curiosity angle that
pulls hard, then change your meta description accordingly.

And keep testing. As Drayton Bird said:

Keep your head up,
Mike

I think it is also important to create a description that will help inspire action within the searcher. You will probably do this by taking Iconik's above recommendations. They are awesome, by the way! Using SEO and those three bullet points will really help.