The promise of better ROI through more sophisticated targeting has fueled the recent acquisitions of audience measurement/analytics firms. Meanwhile, the proliferation of companies in the analytics space has spurred consolidation the last few months. In the case of Adobe, buying Omniture will give its content creation tools much more appeal. This is especially important as Adobe looks to shift its business focus from the desktop to the internet and mobile web. Plus, Omniture comes with a client list that includes just about all the top web publishers.

When the acquisition closes, Omniture’s CEO, Josh James, will join Adobe as SVP of the new business unit, reporting to Adobe’s president and CEO, Shantanu Narayen. The deal is expected to close this fall. The $21.50 per share offer represents a premium of 45 percent over Omniture’s average closing price for the last 30 trading days through yesterday’s close.

Earlier this year, WPP Group invested $25 million in Omniture, and announced that the two had planned to collaborate on a consultancy service. It’s not clear whether that partnership would be severed as a result of this deal, though it appears to be Adobe’s call now.