Following the recent publication of the All-Wales Conventions polling data, I looked up the comparable polls on this subject for the last few years, which showed:
May 07 Yes 47% No 44% Yes Margin +3% (BBC)
Feb 08 Yes 49% No 42% Yes Margin +7% (BBC)
Dec 09 Yes 48% No 35% Yes Margin +13% (AWC)
Feb 09 Yes 52% No 39% Yes Margin +13% (BBC)
(The dates are when the polling was conducted, not when the poll published)
I understand that Labour want a +20% margin before they risk a poll, but things are certainly headed that way, and we could be on target for a 2010 referendum after all.