Yahoo! notified advertisers today that now would be a good time to start revamping ads. The three major search advertising platforms all have different codes and different sizes.  As Yahoo!’s email points out, an ad’s headline can be 40 characters long on their site, but only 25 characters over at Microsoft.  Don’t think that’s a big deal?  You probably haven’t written a brilliant 27 character headline then.

And don’t get me started on Facebook, fast becoming a favorite place for me to advertise local businesses, but with its own rules.   Facebook hasn’t bought anyone yet so we only have to worry about the Yahoo-Microsoft “transition” this year. If an agency is NOT running your Yahoo! ads, everything you need to know is at their “Transition Center“.

Here’s what I can tell you with certainty:

1.  There won’t be Yahoo! text search advertisements.  You’ll be migrated to Microsoft adCenter.

2.  If you have Excel, there are some awesome DIY tools at adCenter for anyone to use so make use of them.

3.  Put your transition plan in place now.   If you’re running on Yahoo, test ads with MSN lengths, or better, open an adCenter account and start learning their platform.

Your takeaway as a small businessperson is that Yahoo! search advertising is going away.  If that impacts your business, you need to plan for it now because Yahoo! says this change will happen before the 2010 holiday season.  That’s only weeks away.