Top online marketing tactics for last year (according to the MarketingSherpa research) include:

• Behaviorally targeted ads favored: Still a favorite, marketers say they will be investing more in them in 2008.

• House lists top paid search: More marketers reported success with house email lists than paid search ads — a reversal from a year earlier.

• Test, test, test again: Marketers are measuring and testing more in almost all categories surveyed.

• SEO begets strong ROI: Search engine optimization is delivering a strong return on investment, according to more than half of the marketers surveyed.

• Viral gains converts: Agencies are urging marketers to explore viral marketing and advertising in mobile phones, online video sites and virtual worlds.

A good bit of time was dedicated to discussing viral marketing, too – especially viral video.  Among the observations made:

• 93% of marketers said agencies recommend either an increase in spending or begin spending on viral video.

• 87% reported recommendations to start or increase viral marketing on social networking sites.

• 62% said agencies advised advertising in games and virtual worlds – the highest number of recommendations for a first-time budget while paradoxically attracting the highest number of recommendations to decrease spending. This confusion clearly reflects the medium’s unproven status.

• 60% saying they are urged to try wireless ads on mobile networks –- it came in second in first-time budget recommendations.