The fluctuation of prices generally is something that facinates me.
I wouldn't be certain, but in the case mentioned above, I'd guess that the price increase is to do with the fact that more people will be shopping at the weekend, rather than earlier in the week. Plus, coming up to the Easter holidays, consumers might like to have that new product purchased and installed beforehand.
Therefore, with the expected higher demand, and the fact that most Irish consumers would rather have their luxury goods instantly rather than shopping around for best value for money, this retailer is rightly taking advantage.
In the early days of online booking of flights and hotels, there was a similar fluctiation of prices based on when people were logging on and buying things. During the day, when lots of people had internet access at work, you could get flights and hotels at a certain price. Whereas if you'd logged in in the evenings (when lots of people didn't have access to the internet at the time), you'd get the same flights and hotels at lower prices.
Another thing to watch with Dixons/Currys/PCWorld (all the same company), is the variation of prices and offers between their Irish stores, even just around the M50. About a year back, was looking for a tv with a mate, and discovered tv at a certain price in Blanchardstown, and Liffey Valley had the same tv for €50 less, plus a free DVD player.
Mary Harney WAS right. It pays to shop around. Even between outlets of the same chain.