There are three basic reasons, why you should start advertising on bing. First, It, combined with Yahoo, has good traffic which is increasing day by day. Second, It has lesser competition in many areas, because most of your competitors ignore it. Third, for many advertisers, for different reasons, it is their only way of advertising online. However, blindly switching to it may bring bad experience to you. There are some basic differences between the two, which has to be kept in mind.
Bing Yahoo ads do not recognize broad match modifier.
If you have imported your adwords campaign into bing, this is the first thing you need to rectify. The Broad match modifier (+keyword), should be altered suitably for good targeting. Also, importing the adwords campaign is not a good idea. If you want result and not just presence on bing, you should build your campaign from scratch, instead of importing it.
PS: Bing rolled out modifier for Broad matches in phases, starting somewhere, in 2012. Now all Bing accounts support Broad Match Modifier.
Bing bid Auction is different from Google
Whereas, on Google, ads are ranked according to the ad rank, and advertisers pay based on quality score, on Bing ads first enter auction based on bids and then pay taking into account quality score of participating ads. So, while an ad with low bid may enter the first page auction, if ad rank is high, on google. On bing ads will first enter the auction based on bids and then pay according to position & Quality score. So a low bid ad, despite high quality score may not qualify to enter auction on bing first page.
So, on bing, you must bid keeping in mind the position of ad and also keep tab on what percent of bid amount you are actually paying to understand relative quality of your ad/page in comparison to your competitors. High Bid with Highly relevant page and ad is the key to Bing Success. Better the page, cheaper it becomes.
Negative keywords are only phrase and exact
All the keywords, you add as negatives are by default treated as phrase match, not broad as treated by google. So, you may need to make the list longer.
More caution needs to be taken with broad matches
Broad matches on bing are rudderless, you can only add negatives to restrict them. Hence, better rely on Phrase and Exact for good targeting. Let the list grow longer.
Content cannot be targeted by domain, you can only exclude them
Don't try content targeting if you are not running a very big budget campaign, Or you know all the bad part of the network, where you should not be. Only if you have surplus ad budget which you may experiment with, you should foray into bing content and keep a steady watch on it.
Mainline ad Formatting
Unlike Google, Bing has Only one line of ad that breaks into two while displaying. Also, unlike Google, which may not honor the first dot as break for serving ads in mainline, Bing will pick the sentence before first dot to serve along with header of ad. You may use this feature to show your Toll Free No. !