Like thousands of other people, I am still exploring the site myself but I can see the potential for some great genealogical evidence being published on here in the future. Tempting as it is to dive in, searching willy-nilly for names and places (Yup, I did too!), I recommend you take the time to peruse the User Guide, which you can find on the Help page. This will help you understand the significance of the coloured dots in particular. The Help page also has the beginnings of some good research background advice too.
I like the idea of an "Inventory of Loss" (largely based on Herbert Wood's 1919 guide) and an "Inventory of Survival", created by the project team to describe the replacement documents in context. The concept of Gold Seams is also an interesting one, whereby major archive series are presented as a whole and presumably, we are invited to mine for treasure. The 1766 Religious Census is one of the first ones given this treatment under the Genealogy tab and I welcome the ability to access and learn about this material through a well written historical background and varied illustrative images. Under the Researchers tab, you will find the Cromwellian Surveys, which I can't wait to get stuck into properly to solve some place puzzles. It's important to note that much of this material is also available elsewhere but in perhaps a more fragmentary format, so this way of presenting the material could prove to be much more accessible.
As this is the launch version, there are many pages that are underdeveloped, so you may find yourself running into quite a few dead-ends. I found this a lot in the proto-catalogue that appears under Browse the Treasury. Lots of partners, many teasing you with labels to content but no links as yet. Be sure to check out the Partners via one of the white on black links at the bottom of every page and there are lots of useful contact details there.
I've blogged enthusiastically before about the Beyond 2022 project, which is the driving force behind the creation of the Virtual Treasury. The team drew together experts in emerging digital technologies and archiving, who are both prone to talking in their own languages. And therein lies my only niggle of criticism about this launch version. The current site copy seems to be liberally peppered with technical jargon and the Glossary has a smattering of terms - "Chunking"? "Stitching"? - that I just know where invented by programmers in a project management meeting and stuck (I know, I attended enough in an earlier life.) One to look out for though as it hopefully becomes a more frequent label is Born Digital i.e. a record created in an electronic format that has never existed in printed or physical format. I look forward to seeing what appears under this category in the future.
Griping about language aside (but why all the American spellings?), this site is very exciting and has the potential to be a hugely valuable addition to the freely available online content that can solve your Irish people puzzles. Bookmark it and keep up with the News page to learn about new content.