Do you ever include flash on a landing page or do you fear even that could cause a distraction to the visitor, or have you found it works on some landing pages to keep them interested for those first few seconds?
Make sure the flash banners are not too big, because the loading speed of the landing page can influence the QS and you might get slapped. As for the design, dunno... I never used flash... and to be honest I rarely saw flash on landing pages.