THEN (2005 General Election Result)
Labour 35.3%
Conservative 32.3%
Liberal Democrats 22.1%
NOW (based on independent poll of polls)
http://www.ukpollingreport.co.uk/blog/uk-polling-report-averageLabour 26%-34%
Conservative 35%-40%
Liberal Democrats 15%-21%
based on the latest polls.......
worst case scenario for Labour and best case scenario for Conservative would result in a 21-25 seat majority Conservative Government
worst case scenario for Conservative and best case for Labour would result in a Labour majority of 6 seats

my guess would be we're somewhere the two extremes but looking at it in more detail, the tories at best are sitting on 40% if that drops even 1% to a 39% share of the vote, we're looking at a hung parliament
you can have a play around with the swingometer here
http://www.telegraph.co.uk/news/newstopics/politics/2432632/UK-General-Election-2010-political-map.html