Bad news, especially for those whose New Year resolutions included starting their Irish genealogy research...
The Griffith's Valuation section of the free AskAboutIreland website is inaccessible and will remain so in the short term. The official note on the site says: "This service is currently undergoing maintenance and performance upgrade. We anticipate it will be available again in a few weeks." (See UPDATE 3 January below.)
Lack of free access to such an important 19th-century collection is a huge blow (see UPDATE 4 January below). Let's hope the upgrade will be swiftly completed. It is much needed, to be honest, but I'd rather have slow access to this collection than no access.
Online alternatives are on pay-to-view/subscription sites:
Griffith's Valuation pages for advice about using this invaluable land and property resource.)
UPDATE, 3 January 2014: I've spoken to the team behind AskAboutIreland today. No additional or enhanced material is being added to the Griffith's Valuation section of the site. The 'maintenance' downtime is needed while the system/program that runs the section undergoes a performance upgrade. A meeting will be held next week with the technical team to establish the necessary time schedule for this work to be carried out and it is hoped (but certainly not guaranteed) that it won't extend much beyond the end of this month.
UPDATE, 4 January 2014: I've been reminded by Shane Wilson on Boards.ie (many thanks, Shane!) that the excellent Failte Romhat website has a searchable version of Griffith's Valuation. It's very basic, and has no images, but it is free and will be useful to many during AskAboutIreland's downtime. (If you have Dublin ancestors, check out Shane's website. It has many unusual Dublin resources.)