The coast of Ireland is beautiful, and the cliffs of Moher are spectacular. Other than that, I don't know that I'd say that there really IS any scenery in Ireland, just lots and lots of sheep.
Having been quite thoroughly sacked on several occasions, most of the monuments in Ireland are pretty well destroyed. The best exceptions are the megalithic monuments like Newgrange, Knowth and Dowth (all in very close proximity to each other, near the town of Drogheda). Ireland is actually covered in these prehistoric monuments, but very few have become tourist attractions. Though Newgrange is bigger and about 1000 years older than Stonehenge (in England), virtually nobody has ever heard of it, whereas Stonehenge is quite famous. Go figure. There are a few nice cathedrals in Ireland, but I was so sick of cathedrals by the time I got to Ireland that I didn't really visit many of them.
In my experience, Irish weather is an absolute drag. I hear that in the height of summer it occasionally gets warm, but that it's still generally cold and wet, all year round. When I complained about the weather (which I tried not to do TOO much, but sometimes I just couldn't help it), I was usually told plainly "you're in the wrong country."
Irish prices are very similar to UK prices. The Irish pound (Punt) is usually just a touch lower in value than the UK pound (Sterling), about 0.85 sterling to the punt. Adjust the price tags accordingly, and the actual values of products and services are about the same. It ain't cheap, but you could do worse. Irish youth hostels are generally a bit cheaper than UK youth hostels (the listed prices are very similar, but taking punt vs. sterling into account, Irish prices are cheaper), and generally just as good.
Irish food is almost identical to UK food: very greasy, very fattening, and most Irish hate vegetarians (especially American vegetarians, who tend to be a bit fanatical about it). Lots of deep-fried foods, lots of meat. Irish people on a budget will eat lots of beans, eggs and potatoes.
For a Western culture, you couldn't ask for much friendlier or more hospitable people than the Irish. I camped all over Ireland, just going up to farmers' doors and asking if I could camp in their fields. I was never turned down, and I was always invited in for at least a cup of tea, sometimes even a meal.
If you ask me, the biggest reason to travel in Ireland is just to meet some really friendly, wonderful people. The scenery isn't that spectacular and there aren't that many interesting monuments, but you'll have a great time just shootin' the breeze with the locals.
The youth hostels and whatnot were moderately clean, but the cities are quite grey and dingy, and you'll find much more trash laying around than you find in the neighboring UK.
A lot of green, rolling hills, and not much else, except on the coast, which has green, rolling hills until you hit the cliffs, which drop straight into the ocean.
Road conditions in Ireland are HORRIBLE. The roads are MUCH too small (two-way roads were just barely big enough for some of the huge trucks to get by me, and I was on a bicycle. I can't imagine how they pass any cars that happen to be coming the opposite way.), and tend to be in a terrible state. When I first entered Ireland, one fellow asked me "so, how do you like the Irish roads?" When I told him I hadn't hit any potholes yet, he replied "oh, just wait... you will." The Irish complain bitterly about the state of their roads, and with just cause. The roads in Greece (the 2nd poorest nation in the EU) were generally better.