What do you think is the most important thing to consider in writing ad copy? Do you think having the keyword and price or something that will entice the user more like a special offer? Let me know what you think.
When writing ads you need to consider the relevancy first and keep other things secondary. Because relevancy is very much important in achieving better quality score for keywords. Better quality score increases the ad position and reduce the cost per click. So you should have your keywords in the ad text and then think some angle of attack. The best way to write ad is to Ask question in heading. Then show benefit in 2nd and 3rd line and then put a call to action statement in the 3rd line as well. If you will put in the price of product it will reduce the clicks and you may be able to increase the conversions. But its a matter of testing different things.
From my perspective as an advertising copywriter, I would recommend that you focus on the key benefits of the product or service you offer. What can you do for them? When I write, I always put myself in the reader's shoes, because they don't care about me, or about the company I'm writing for. They want to know what's in it for them. If you'd like some quick tips, you might want to check out the blog I have at GoogleAdWriter.com. Hopefully you can find something useful there.
Bedhead said it. Ads showing benefits are the ones that get clicked on. Having the keyword in the ad should happen naturally. If I search on "short wooden widget" and you bid on that keyword and you sell them, it's kind of hard not to mention at least wooden widget in your ad. There are some exceptions but never put price in the ad. If you have a special offer, use it. Here's an example: Wooden Widgets Free thingamabob if you buy 3. These widgets make women crazy. The title says I have widgets. It gets bolded since both words are part of the keyword. I usually put a feature on the first description line, in this case the free offer. It is not a benefit which usually I put on the second description line. Test different features and benefits. Mix and match. Try the benefit line before the feature. Little changes can make huge differences in click rates. Get my book which goes into the nitty gritty details.