Given that the referendum on Scottish independence is now very near - September 18 - I think people will be interested in the new Survation poll. See http://ukpollingreport.co.uk/ 29 August entry for full details and further discussion. The result when 'don't knows' are accounted for is given in the title of this entry.
It is worth treating all polls on this issue with some caution; the polling companies have never polled on such an issue and so, obviously, have no record of knowing if their methodology will accurately - or even reasonable accurately - reflect the final outcome.
The Guardian newspaper has an interesting analysis about the opinion poll result and why the increased yes vote may be happening. See http://www.theguardian.com/politics/2014/aug/30/independence-referendum-scotland-vote-women
And for a useful Al Jazeera article comparing the Scottish referendum position with the independent Quebec (Canada) 1995 referendum position see http://blogs.aljazeera.com/blog/europe/scotland-seeing-quebec-effect
And for a 2 September Guardian article see http://www.theguardian.com/politics/2014/sep/02/scottish-independence-yes-campaign-poll-boost - the key point being affirmation of the narrow gap between the 'yes' and 'no' sides as shown by further polls.