NSW are IMO unlikely to win whilst Slater, Cronk, Thurston and Smith are all available and close to their peak. Injury permitting, all have another 3 years left in them, and given guys like Hannant, Scott, McGuire, Thaiday et al will be around to lead the pack, I don't see why QLD can't keep winning til our spine reaches their age 32 year (I think all are currently in their age 29 year).
Once that decline happens, it honestly wouldn't surprise me to see NSW dominate for 5 years or so. Not to a QLD extent, but dominate all the same. Only DCE really impresses me as a young spine player, and we still got dominated by NSW even when we had Lockyer, so it's not like he's going to be enough. Plus NSW always have the bigger talent pool to select from. That our pool of talent is of such higher quality in this 10 year span (2005-14ish) is IMO, an exceptionally rare anomaly we are unlikey to see in many decades.