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.

MOST NOTEWORTHY: The U.S. food industry, Mylan Labs, Amerigroup and Isle of Capri were today's noteworthy upgrades:

• BMO Capital upgraded the U.S. food industry sector to Outperform from Market Perform to reflect the group's defensive nature, the recent valuation contraction, and predictable earnings growth. General Mills (NYSE: GIS) is the firm's top pick in packaged food, and they raised Kellogg Company's (NYSE: K) target to $59 and Kraft Foods' (NYSE: KFT) to $36.
  
• Credit Suisse upgraded Mylan Laboratories (NYSE: MYL) to Outperform Underperform, as the firm believes investors are "too negative" on the Merck transaction. The firm said the company is well-positioned long-term to be a leader in the global generics industry.
• Credit Suisse also upgraded shares of Amerigroup Corporation (NYSE: AGP) to Outperform from Underperform, as they believe the company is poised for better than expected margin improvement in 2007 and 2008.
• Isle of Capri Casinos Inc's (NASDAQ: ISLE) rating was upped to Buy from Hold at Morgan Joseph, citing indications of progress in the company's turnaround.

OTHER UPGRADES:

• Epic Bancorp (NASDAQ: EPIK) was upgraded to Buy from Hold at Sandler.
• Aruba Networks Inc (NASDAQ: ARUN) was upgraded to Outperform from Sector Perform at Pacific Crest.
• Lazard upgraded shares of Amylin Pharmaceuticals (NASDAQ: AMLN) to Buy from Hold.
  
• BMO Capital upped shares of Goodrich Petroleum (NYSE: GDP) to Outperform from Market Perform.

One of the hottest IPOs of the year is Aruba Networks Inc. (NASDAQ: ARUN), which is up 82.5% since its debut in late March. The company builds technologies to secure large corporate wireless networks. With the proliferation of devices – such as Research in Motion's (NASDAQ: RIMM) BlackBerry – it is a big market opportunity.

Well, another firm wants a piece of the action: Aerohive Networks.

In fact, the company recently raised its second round of venture capital for $20 million. The lead investor is the venerable Kleiner Perkins

Aerohive develops so-called "cooperative control" wireless LAN (WLAN) access points, which it makes it easier for companies to deploy wireless services – and at lower costs. This is done by sharing information in optimized groups, which are called "hives."

No doubt, Aerohive faces intense competition, such as from Cisco Systems Inc. (NASDAQ: CSCO). But in the WLAN market, there is always room for a better product.

Besides, Aerohive has a top notch management team. Keep in mind that their last deal – NetScreen – sold for a cool $4 billion to Juniper Networks (NASDAQ: JNPR).

To check out more recent venture capital fundings, click here.

Tom Taulli is the author of various books, including the Complete M&A Handbook and the EDGAR-Online Guide to Decoding Financial Statements.