Change in RatingsJanus ( JNS) downgraded at Goldman Sachs to Neutral from Buy due to asset deterioration and margin compression, leading to lower earnings in 2009. Note increasing risk of asset outflows. Price target cut to $11 from $18. RadioShack ( RSH) downgraded at Goldman Sachs to Neutral from Buy. Also note cyclical vulnerability and recent outperformance, leaving valuation less attractive in light of lower earnings estimates. Price target lowered to $16 from $20. Raytheon ( RTN) upgraded at Merrill to Neutral. $62 price target. Lower tax rate and increased buybacks will add to future earnings. Trimble ( TRMB) downgraded at Deutsche Bank from Buy to Hold. $18 price target. Company warned of lower results, and estimates are also being cut, as E&C customers are being hurt by the credit squeeze. Zimmer ( ZMH) downgraded at Morgan Stanley from Overweight to Equal-weight. Company is losing market share and won't see significant earnings leverage for another year. Stock Comments/EPS ChangesAltria ( MO) numbers cut at Morgan Stanley. Shares now seen reaching $24. Estimates also lowered, to reflect lower domestic cigarette volumes. Equal-weight rating. Nasdaq ( NDAQ) added to Goldman's conviction buy list based on strong near-term metrics driven by high volatility, as well as a solid earnings outlook for 2009 in spite of potential volume declines. View recent pullback as buying opportunity. Price target at $38.