Just tried it there myself and I cannot get even to the log in page. Tried again and get in to login screen but then there is some mush on the page. I'd say give them a ring if you need something urgent otherwise try later.
Are you using the new(ish) link for internet banking? They updated it a few months ago and both could be used since then. However this morning I noticed that the old version, which I had bookmarked, is no longer working. Go to www.aib.ie and log on via the relevant link rather than from a bookmarked one. Other than that I've had no issues.
Had the same problem this morning. WAs able to log in to see my balances but when I clicked on an account for more information all I got was the "page cannot be displayed" page.
Very slow to log on, but when you want to transfer money etc... just goes to blank page. Tried a few times, but nothing. Even tried different browsers, same...
I'd imagine some of the users above have managed to do some banking since 2009...
You may need to install the latest Java from Java.com and then (assuming Windows) go in to the Java applet in the Control Panel and on the security tab bring the Security Level slider to Medium.