I don't put much store in opinion polls, but if true it would only indicate roughly what you would expect to happen at this point in the parliament - 32 % isn't that much lower than Labour got in the 2005 General Election and all it would suggest is that the Liberal Democrats are having a reversal -
tactical voting could see them holding onto many of their current seats, indeed it is even possible that if they got 17 % of the
vote that if it focused in an area that they could actually
end up with more seats, where the switches in support are occuring is crucial - if they are focused then if the Conservative Party were to get 39 % then it might still result in them getting fewer seats than Labour or in extremis winning a 150 seat majority or so?