MOST NOTEWORTHY: EMC Corporation, Tesco PLC, SL Green Realty, Ariba and Motorola were today's noteworthy upgrades:

• EMC Corporation (NYSE: EMC) was upgraded to Outperform from Peer Perform at Bear Stearns on valuation. Shares were also upgraded to Buy from Hold at Citigroup after coming off restriction to reflect the long-term benefits of virtualization and valuation.
  
• Tesco (OTC: TSCDY) was upgraded to Buy from Hold at Citigroup on valuation and the company's growth prospects.
  
• SL Green Realty Corporation (NYSE: SLG) was upgraded to Buy from Hold at Keybanc based on valuation. The firm views concerns regarding NYC office demand as overblown.
  
• Cowen expects FY07 to be a tough year for Ariba Inc (NASDAQ: ARBA) as benefits from the on-demand subscription model are realized. The firm upgraded shares to Outperform from Market Perform.
  
• Motorola Inc (NYSE: MOT) was upgraded to Outperform from Sector Perform at RBC Capital citing firming trends in its handset division.

OTHER UPGRADES:

• Jefferies upgraded Optium Corporation (NASDAQ: OPTM) to Buy from Hold.
  
• JP Morgan upgraded Susster Holdings Corporation (NASDAQ: SUSS) to Overweight from Neutral.
  
• Thomas Weisel upgraded Vishay Intertechnology (NYSE: VSH) to Overweight from Market Weight.
  
• Royal Caribbean Cruises (NYSE: RCL) was upgraded to Strong Buy from Outperform at Raymond James.

Opnext, a maker of laser diodes, optical modules and pluggable modules, is expected to go public this week, and will trade under the symbol OPXT. Opnext is the second optical component company to come public in the last four months. Optium Corporation (NASDAQ: OPTM), a Chalfont, Pa-based company, came public in October 2006 at $17.50 and is now trading at $24.95.

Opnext has been funded by Hitachi and venture capital firm Clarity Group. Hitachi will be transferring some 670 patents to this start up.

The stock is supposedly going to be priced around $14 per share. With only two optical companies recently coming public, as one would expect, the financials for the company are pretty solid.

Supposedly, Opnext is strong in the 10-Gigabyte optical space and also has product for 40 gigabyte technology.

These optical components are very cyclical, as are most new higher growth industries. The upcycle in this space appears to be still in its early stage. It may be worth a spec on this IPO.

Last night on his MAD MONEY show on CNBC, Jim Cramer said there was no reason to wait for the J.P.Morgan Biotech conference, because he already had the stocks to play. This makes for many short-term and long-term trades for the year, and that is why it is important. He had a jump on it, he said. His #1 biotech pick going into and coming out of the conference was what he focused on.

Thermo Fisher Scientific Inc. (NYSE:TMO) presented today at 11 a.m. and Cramer had said he would buy it ahead of its presentation. It's a one-stop shop for all the scientific instrument and analytic needs now. Here are the expanded comments on TMO.

Cramer earlier picked Gilead Sciences, Inc. (NASDAQ:GILD) as one to buy going into the conference, and the Street's caution on its Myogen, Inc was wrong. Myogen was his favorite pick in biotechs in 2007. Here is the larger commentary on GILD.

In a call in, Cramer panned Ligand Pharmaceuticals (NASDAQ:LGND) and said he wasn't worried about a small portion of insider ownership in Genentech, Inc. (NYSE:DNA) and Amgen, Inc. (NASDAQ:AMGN) because they are so huge.

Cramer did not re-mention Savient Pharmaceuticals, Inc. (NASDAQ:SVNT), his #2 runner-up for speculative stocks in 2007.

OVERLOOKED IPO OF 2006

Cramer also wanted to review some IPO's of 2006 that didn't work out well at all to see if they were overlooked. His #1 overlooked IPO is Optium Corp. (NASDAQ:OPTM). Because of all the telecom equipment-providers this has been lumped in with the bad ones. It went public in October 2006 and it is a supplier of fiber to the home and Triple Play. Here are the rest of his comments.

Jon Ogg is a partner in 24/7 Wall St.,LLC; He does not own securities in the companies he covers.