NEW YORK ( TheStreet) -- CHANGE IN RATINGSAlcon ( ACL) downgraded at Citigroup from Buy to Hold. $165 price target. Valuation call, as the stock will be driven negotiations with NVS. Cogent ( CCOI) upgraded at BofA/Merrill to Buy from Neutral on economic recovery and valuation. Price target boosted to $14 from $10.50. Cree ( CREE) downgraded at Morgan Joseph from Buy to Hold. Company should post in-line earnings, and the stock is already pricing in growth in the LED lighting market. Lennar ( LEN) upgraded at Barclays to Overweight from Equal Weight as analysts believe there is further upside to be seen this year. Price target increased to $20 from $17. 2010 and 2011 EPS estimates set at -$0.07 and $1.04, respectively. Netsuite ( N) upgraded at Morgan Stanley from Underweight to Equal-weight. Industry trends have improved and the stock has shed its premium valuation. PPG Industries ( PPG) upgraded at Citigroup from Hold to Buy. Company should benefit from increased auto production in 2010. $71 price target. Stock also added to the Top Picks Live list. Spectra Energy ( SE) initiated at BofA/Merrill with a Buy rating and $24.50 price target. Favorable pricing and processing spreads, analysts said. Toll Brothers ( TOL) downgraded at Barclays to Equal Weight from Overweight. Continued lack of profitability, driven by TOL's longer cycle times, analysts said. Price target trimmed by $2 to $21. 2010 and 2011 EPS estimates set at -$0.69 and $0.16, respectively. Tyson Foods ( TSN) upgraded at Credit Suisse to Outperform from Neutral on valuation. Price target lifted to $16 from $13. 2009 and 2010 EPS estimates raised to $1.05 and $1.20, respectively.