Analyst upgrades:

• Jefferies upgraded Aruba Networks (NASDAQ: ARUN) to Buy from Hold following the company's Q3 results to reflect improved visibility. The firm raised its target price to $6.50 from $3.
• Citigroup upgraded Mosaic (NYSE: MOS) and Potash (NYSE: POT) to Buy from Hold and Agrium (NYSE: AGU) to Hold from Sell as it believes stronger grain fundamentals more than offset China contract risk. The firm raised its target on Mosaic to $72 from $48, on Potash to $145 from $83 and on Agrium to $55 from $36.
• Fulton Financial (NASDAQ: FULT) Was upgraded to Market Perform from Underperform at Keefe Bruyette.
• Rio Tinto (NYSE: RTP) was raised to Neutral from Sell at Goldman.
• Noble Corp. (NYSE: NE) was upgraded at Deutsche Bank to Buy from Hold.

Nordstrom (NYSE: JWN) is expected to report Q2 EPS today after the market close. JWN August 30 straddle is priced at $2.90, September 30 is at $4.40. JWN September option implied volatility of 58 is above its 26-week average of 52 according to Track Data, suggesting larger price movement.

Red Robin Gourmet (NASDAQ: RRGB) is scheduled to report Q2 EPS today. RRGB August 30 straddle is priced at $2.60, September is at $5.15. RRGB September option implied volatility of 64 is above its 26-week average of 52 according to Track Data, suggesting larger price movement.

Heelys (NASDAQ: HLYS) is recently up 68 cents to $5.55 in pre-open trading. Skechers (NYSE: SKX) made an acquisition proposal to acquire HLYS for $5.25 per share ($142 million) in cash. HLYS, wheel-in-the-heel footwear marketer, closed at closed at $4.87. HLYS traded at a record high of $40.09 in February 2007. HLYS over all option implied volatility of 77 is near its 26-week average according to Track Data, suggesting non-directional price movement.

Option Update is provided by Stock Specialist Paul Foster of theflyonthewall.com

MOST NOTEWORTHY: Durect, Red Robin Gourmet and ViroPharma were today's noteworthy initiations:

• RBC Capital thinks Durect's (NASDAQ: DRRX) overall portfolio is very attractive and started shares with an Outperform rating and $7 target.
  
• Red Robin Gourmet (NASDAQ: RRGB) was initiated at Jefferies with a Buy rating and $40 target. The firm believes the company has one of the few stable earnings stories in the sector, which should warrant a valuation premium in the current environment.
  
• JMP Securities believes ViroPharma's (NASDAQ: VPHM) valuation reflects several negative scenarios and notes that earnings will likely remain positive and that the company has a strong balance sheet; shares were initiated with an Outperform rating and $12 target.

OTHER INITIATIONS:

• Harmonic (NASDAQ: HLIT) was assumed with an Overweight rating and $14 target at Stephens.
  
• ThinkEquity initiated Intuitive Surgical (NASDAQ: ISRG) with a Buy rating and $360 target.
  
• Broadpoint started Salesforce.com (NYSE: CRM) with a Buy rating.