Paid search marketers should review their keyword lists to ensure the different ways Yahoo! and Bing normalise terms do not leave "gaps" in their campaigns.
This is according to Jeremy Hull of Search Engine Watch, who said anyone who has tried to export their pay per click marketing keywords from AdWords to Yahoo! will have noticed "between 30 and 50 per cent" of the list is rejected.
For example, all but one of the terms "man shoes", "men shoes", "man shoe", "man's shoes" and "men's shoes", which could all be used on the Google service, would be kicked out by Yahoo! because its system considers them all to be essentially the same term and matches would apply to any of the queries.
As a result, marketers who transfer their Yahoo! terms to adCenter as part of the Search Alliance transition will be "leaving plenty of gaps".
Indeed, Mr Hull said it could be more effective to import a set of AdWords keywords to adCenter.
Nevertheless, some tweaking would still be required as the Microsoft platform rejects possessive versions of existing terms.
"The best idea is simply to remove possessives from your keyword list to avoid confusion," the expert said.
Paid search accounts are expected to have been switched from Yahoo! to adCenter by the end of this month.
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