Update addressing some questions/comments:
(1) The map specifically shows the frequency of blond hair; so yes the frequency of light hair in general will be higher.
(2) The map is adapted from Biasutti's Razze e popoli della Terra. The data was originally collected by Ridolfo Livi in 1859-1863.
(3) The Biasutti/Livi map shows a higher frequency of blond hair in Corsica than in Sardinia. In keeping with the apparent pattern elsewhere in Italy, the frequency of R1b appears to be markedly higher in Corsicans than in Sardinians (in this paper, "HG 1" in combination with "HG 22" roughly corresponds to R1b).
(4) "Does R1b necessarily correlate with light hair?" In Italy it pretty clearly does. If you mean am I suggesting a strict correspondence between light hair and haplogroup R1b, obviously I am not. Looking at Europe as a whole, I doubt much of a correlation exists. But the evidence is consistent with the bearers of R1b (or more specifically subclades of R-L11) being lighter than the previous inhabitants of Italy. This doesn't mean the original carriers of R-M417 and some subclades of I weren't probably also lighter-haired, or that as R1b spread throughout Europe and mixing occurred, R1b always remained associated with light hair. It does tend to add yet more weight against attempts to link R1b in Europe to migration of Neolithic farmers from Anatolia, but dispensing with that question for good awaits large, high-resolution studies of ancient and modern DNA.
"haplogroup R1b is found in some of it's highest concentrations among European peoples in Spain and Portugal -- two countries hardly known for blondes."
Within Iberia, though, it's certainly possible the pattern will hold. Among Iberians, Basques have some of the highest frequencies of both R1b and blondism. According to Coon: 'The French Basques are by no means all brunet; Collignon finds 22 per cent of blue eyes, 44 per cent of "medium," and 34 per cent of dark. Black hair is found in 7 per cent of the group, brown in 77 per cent, and light brown to blond in 16 per cent. Among the Spanish Basques the incidence of blondism is somewhat lower, but the Basques are still light when compared to most other inhabitants of Spain.'