Google have just announced changes to their adwords url display policy in that the display url (which is the url displayed in the ad) must match the landing page url (which is the page that the visitor goes to) with effect from the 1st April 2008:
This could have major implications for Recruiters who link their ads directly to the relevant job description page as sometimes the url for the job description is on a different url.
For example, an international company XYZ may have a XYZ.co.uk careers web site but their recruitment system is on their global XYZ.com domain.
Also, there may be a situation where the XYZ company has their recruitment system hosted by a third party and the the url is a sub domain "xyzcompany.recruitmentsystemsuppliername.com"
In both the above situations Google are saying that the ads will not longer run.
Whilst I can understand their reasoning (see the announcement) I can see major problems ahead for Recruiters in the above scenarios.