Central London-focused FTSE 250 real estate group Shaftesbury said it has seen continuing good demand and letting activity across its West-End villages in the first half, while vacant space is now at an 'exceptionally low level'.In a trading update covering the period between October 1st to date, the firm said that it has "sustained interest from retailers, particularly from Europe and America, seeking shops in our centrally-located villages. Similarly there are many interesting new restaurant concepts seeking space in the West End."Shaftesbury is currently undertaking two major schemes around the Carnaby Street area, just east of Regent Street, which will cost £18m and, when fully let, will produce an additional £2.0m of rental income every year.Meanwhile, the estimated rental value (ERV) of the group's other schemes amounts to £2.3m, equal to 2.8% of its wholly-owned commercial ERV.The ERV of wholly-owned commercial space available to let amounted to just £2.0m by January 31st (2.4% of the total commercial ERV), of which £1.2m was under offer."This low level of available space reflects a particularly busy period for enquiries and letting activity since September," the firm said.However, the number of vacant shops is expected to increase in the early months of 2013 but the company said that this was in line with seasonal patterns of activity.At Friday's annual general meeting, John Manser will step down as Chairman (as previously announced) and will be replaced by current Deputy Chairman Jonathan Lane.