im going to ireland! what should i drink?!

I guess no trip to Ireland's complete without sampling "Guiness" (can be a bit of an acquired taste)
http://en.wikipedia.org/wiki/Guinness

Then I suppose there's also "Caffrey's" or "Murphy's"..... though never tried them personally
http://en.wikipedia.org/wiki/Caffrey%27s…
http://en.wikipedia.org/wiki/Murphy%27s_…

Non-beer drinks that spring to mind..........

Bushmills Irish whiskey - they've been making the stuff since at least 1608
http://en.wikipedia.org/wiki/Old_Bushmil…
(drink either neat or water it down with lemonade)

Magner's cider is another drink brand native to Ireland
http://en.wikipedia.org/wiki/Magners

Check out The Porterhouse in the Temple Bar area: see http://www.porterhousebrewco.com/templeb… Last time I was there they did a great taster tray of various beers (ales, lagers, stouts). Some brewed on the premises too. Lovely! And as a bonus there's normally some really good live music in the evenings too.

As far as native Irish drinks.

Souts:
Guinness
Murphy's
Beamish

Ale:
Smithwicks (pronounced smith-icks)

Cider:
Bulmers (Magners if you are up North) (about 5%)

Most Irish people drink european lagers and beers, such as Heineken, Carlsberg,

woman drink Murphy's stout.

Ale or cider