• by David Goetzl  @dgoetzl, December 27, 2009

Email service providers Responsys and ExactTarget are industry pacesetters, according to Forrester Research's "Wave" study that was released last week.

Forrester wrote in its report that clients "are overall very pleased" with Responsys' continual innovation, while ExactTarget received high marks for an ability to "cater to marketers in any market segment." The research firm conducted evaluations in the second quarter of 15 ESPs. It conducted a survey with results based in part on responses of 218 clients and phone interviews with 48.

Sixty-nine criteria were used to gauge the ESPs, divided into three buckets: current offering, strategy and market presence. Forrester said the 15 ESPs were selected from a potential group of 40, using firms with at least $10 million in global billings and those that send 200 million-plus emails a month, among other benchmarks.

In addition to Responsys and ExactTarget, Forrester listed six other "champions of innovation and sophistication." Within that group, its findings included: e-Dialog has strength in analytics and automation; Acxiom "has been quick to integrate mobile and social functionality" with email needs; and Yesmail offers a "robust tool for managing all aspects of email campaign deployment." Experian Marketing Services, Epsilon and Zeta Interactive were also listed among "leaders" in the "large enterprise" deployment" arena.

Forrester said that Datran Media, Silverpop and ClickSquared "offer competitive options," although they have a focus on "niche parts of the broader marketplace."

Lyris, BlueHornet, Alterian and Emailvision were labeled "safe bets." Forrester wrote: "While these vendors have their individual strengths, they lack features such as advanced segmentation and analysis tools that would meet the demands of today's enterprise-class clients."

In the report, Forrester found that client demands may be intensifying. "Email marketing frequency is growing," the report said, because the channel may be a more efficient tactic, but "soaring sending sizes drive even more price compression in the market." Also, the report said "given the increasing complexity of the email marketing channel -- including the need to integrate email with social and mobile channels -- the call for strategic guidance will only continue in importance."

Marketers also hunger for improved analytics, the Forrester study found.

Among the top five challenges that email marketers expect to face over the next two years, the survey showed that 49% said increasing open and click-through rates, while lower down, 29% said retaining current subscribers.