There are dialects in Gaelic which are maintained thanks to rather large subsidies.
There aren't really dialects in English-speaking Ireland, so to speak - only certain words that some areas use more than others. But the accents are still there.
My own accent (Limerick) is much maligned (think Dolores from the Cranberrys) - but thanks to my mum, the rougher end of the Limerick accent was kind of beaten out of me as a kid - and the part of the city I grew up in was as middle class as you'd get, so none of my peers spoke with a strong Limerick accent.
The really harsh northern Irish accent is not too popular (think Paisley, etc)...you can probably guess why this might be.
Hmmm...let me think, I reckon the midlands accent (e.g. Offaly) gets a hard time - if you remember our last Taoiseach, Cowan - labelled a BIFFO (Big Ignorant F****r From Offaly).
Personally my most disliked accent is the Dublin accent.
My favourite accents would be Donegal, Cork and Kerry.