Shares of Omniture rose $4.49, or 14.2 percent, to $35.96 in morning trading. Earlier, Omniture shares traded as high as $38.57 -- their highest since the company began trading publicly in late June 2006.

Visual Sciences stock gained $2.20I kn12.7 percent, to $18.85 It has traded between $10.44 and $19.86 in the past year.

On Thursday, Omniture said it will pay Visual Sciences shareholders $2.39 in cash per share and a fixed exchange ratio of 0.49 shares of Omniture stock for each Visual Sciences share.

Visual Sciences stockholders will own about 13.7 percent of the combined company when the deal is finalized.

Analysts and investors have speculated for months that Visual Sciences could be bought out, as it said in July that it hired Goldman, Sachs & Co. to weigh a possible purchase after it was approached by strategic buyers.

Also Thursday, in a conference call, Omniture said it expects to beat its previous third-quarter outlook.

In a note to clients Friday, Friedman, Billings, Ramsey analyst David Hilal reiterated a "Market Perform" rating and lowered his price target for Visual Sciences to $18 from $20, saying the adjustment reflects Omniture's offer.

Since the deal combines the top two Web analytics companies, Hilal thinks it could encounter antitrust scrutiny, but will be completed.

"On one hand, the current market is fragmented, with a number of players, and new entrants, such as Google, Yahoo and Microsoft, could become strong competitors. On the other hand, the acquisition of Visual Sciences would join the two largest pure-play Web analytic providers in the industry," he wrote.

Deutsche Bank analyst Tom Ernst Jr. raised his price target to $40 from $28 for Omniture due to "confidence in business momentum" and possible revenue boosts and cost savings from the combination with Visual Sciences.

The analyst holds a "Buy" rating for Omniture.