I think its more of a realisation that Wales is currently far better off as the "and Wales" bit of "England and Wales". Yes, we have our own distinct language, culture and identity (which has survived despite the attempts at wiping it out), and have rebelled against "the English" as much as the other members of the UK over the centuries, but since Thatcher did her thing we have nothing in the way of an economy you could support the night on 4million of us on - we rely on gettingmore from the UK than we give, and most people here know this and see no problem with it. Tourism and agriculture can only get us so far. Yes we still have some coal and some gas in the Irish Sea, massive potential for hydro and wind power, and some heavy industries (most noticably steel production and oil refining) in the south still clinging on by the skin of its teeth but with our main employers being public sector (most signifigantly education and the NHS) we need the Westminster funding to keep things ticking on, even if the levels of funding for our public sector is far less than equivalent bodies in England. Where I live (North West Wales) is particularly nationalistic, but very sparsely populated and almost politically irrelevant in both the Senedd and Westminster, with Plaid Cymru holding seats in both which get traded and bartered in coalition talks every election. The south Wales coast and valleys which are more heavily populated are only slightly less patriotic but red as red can be in terms of socialism (if Labour can be called that still), even more so since the 80's. We are quite happy to be all fierce and patriotic and shit in public, but in private doff our cap and take the cash/gains from Westminster.
However, unlike Scotland, I would strongly suspect that if we were offered independance, we would be more likley to take it than Scotland, probably as we have had far more shit in history from the English that could be dragged up. On the other hand though is the very low turn out in the 1997 devolution election with went "yes" only by a few %.