Google’s pick-up of Postini received mostly positive reviews from Gartner, as analysts Matthew W. Cain and Peter Firstbrook said the acquisition makes Gmail – already “the most attractive component of the fee-based Google Apps suite” – even better looking to businesses turned off by the application’s lack of security and enterprise control.

Here are a few quotes from the analysis. For one, Gartner looks for Microsoft to launch an Exchange software-as-a-service (SaaS) program next year.

“The hygiene and control services also represent a significant ‘upsell’ opportunity for the $50 per user, per year Google Apps suite, but high add-on fees will likely threaten its pricing advantage over Microsoft Exchange — its chief competitor for enterprise seats — which is likely to launch an aggressive Exchange SaaS program next year.”

And with Postini as the latest victim of merger and acquisition mania, look for Cisco and Symantec to try to fill the void in the email security marketplace.

“Postini has been one of the most successful of the hosted hygiene vendors — it competes primarily with Microsoft (which acquired FrontBridge Technologies in 2005) and MessageLabs, a U.K.-based company that also is an attractive acquisition candidate. We expect Cisco and Symantec to directly enter the email hygiene SaaS market in the next 12 to 18 months.

Postini also represents an attractive commercial market channel for Google. The eight-year-old company has 11 million mailboxes under management from 35,000 organizations, representing larger enterprises and, small businesses — the primary target for Google Apps. Postini also maintains a healthy distributor channel which Google might exploit, although it has always favored a direct-sales approach.”

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