Obviously testing different advert copy to improve your CTR will be another good option.
If you have a wide variety of keywords pointing to one page, consider breaking it into multiple pages - one for each topic.
As per square_cat, optimising CTR is vital - test call to action terms in your ad text, or providing USPs that stand out from your competitors.
2. Reduce your bounce rate by having an absolutely obvious next step towards a users goal. Example: make a big button attractive to moderately intelligent chimps and put it near the top left corner of your landing page.
Quality = CTR + (users interested enough go somewhere else on your site)
Cheers
Sid
Obvious next step towards a users goal.
I would think the above only applies when a next step is present. Since I'm typically working with very tight budgets, I've always put the visitor right where they need to be. We don't want them landing on a page that doesn't present them with the ability to checkout. I'll assume that many of use are "selling" something at that landing page, yes? For me, improving the Quality Score would entail making sure the visitor "get's what they came for". The only clicks I want them to make would be the Add to Cart and/or Buy Now/Checkout from that page. :)
Have around 5-20 keywords per ad group. Your ad and the page it clicks through to should be simular. ie. The page content should expand further from the information on the advert.
I also try to match the same keywords triggers to be within the ad and on the page.
eg.
keyword 'buy a car'
advert 'Looking to buy a car?..'
page 'You can buy a car from us..'
If after all this advice you still have rubbish quality scores then its likely Google has a problem with your domain and you need to put your website on another domain name.
[edited by: Seb7 at 10:22 pm (utc) on May 27, 2008]
Usually after seeing googlebot hit the landing page its a matter of seconds before you see 1 or 2 1.00 clicks magically appear