Unscientific BBC survey suggests that fewer people are putting up party posters in the run up to this election than in previous years. There certainly seem to be plenty around here, although red seems a rare colour.
Interestingly, party political posters are exempt from the Town and Country Planning (Control of Advertisements) Regulations 1992 (my favourite piece of legislation to flout, as regular readers will know) provided they are removed not more than 14 days after the election.