On a generally quiet day on the company news front, property groups take centre stage with a series of announcements.None of the news is particularly earth-shattering, but the sector is one of today's best performers nonetheless. Property group Songbird is flying high after saying it has increased its stake in Canary Wharf with the purchase of a slug of shares from Commerzbank for £112.5m.Robert Noel is to leave Great Portland Estates to join the board of rival property group Land Securities as managing director of LandSecs' London portfolio. Shares in LandSecs advance but Great Portland's are lower.And British Land is higher after saying is to put its Broadgate property assets in the City into a joint venture with US asset management group Blackstone Group.Sainsbury's, which yesterday afternoon formally announced the appointment of new chairman David Tyler, who promptly opened his account in the supermarket giant, is among the stocks lifting the food retail sector higher today.Top performing sectors so far todayPharmaceuticals & Biotechnology 8,279.03 +1.62%Food Producers & Processors 4,529.09 +1.39%Beverages 7,254.62 +1.33%Food & Drug Retailers 4,569.43 +1.09%Real Estate 2,176.84 +0.73%Bottom performing sectors so far todayChemicals 4,139.74 -2.18%Industrial Transportation 2,011.41 -2.17%Forestry & Paper 3,310.04 -1.98%Electronic & Electrical Equipment 1,534.29 -1.31%Personal Goods 8,679.42 -1.28%