At this point it is, yes, a lot of backward counting.
I would LOVE an app that lets you plug in a real world day/time and it gives you the Glitch day and visa versa.
The developers have actually put up some sample code on how to convert between real world and Glitch time. I looked around and thought I might have a go at writing something with that.
Two hours later...
Okay, that took a lot longer than I thought. Still, here's the 'app' that converts real world datetime to Glitch datetime. All it's missing is a list of the names of the days of the week. I'll update it when I can get my hands on that list. Have fun: http://jsfiddle.net/bGMRv/12/embedded/result/
Edit: I've fixed that bug and added in some comments to the code. If you want to play with it it might be better to use the 'Fork' button which jsFiddle provides.
Edit: I tried doing some calculations in regards to the day of the week. My mathematician fiancé is in the hospital so I didn't want to trouble him with something like this, but here's my parsing of it: Every year has 308 days, but Recurse isn't counted when you consider the named days of the week. Effectively that gives us 307 named-days-of-the-week per year. Since there are 8 days per week, we have to calculate 307 mod 8, which is 3. This means that Year 1 ended on Weddingday*, Year 2 ended on Standday*, and so forth; we need to only shift the value of the day of the week (starting with 0 for Hairday and ending with 7 for Fabday) by 3 each year. I don't know how that translates into programming, though, or how we would use that to calculate the day of the week for any given date when Recurse is accounted for in the given date calculations.
*That's assuming that my calculations are right! Correct me if I'm wrong.
Edit 2: Ha, on rereading that, it sounds like you have that part down, and when I looked at the coding, it was obvious where that part fell. Still, a good exercise in modular arithmetic! The names of the days of the week, in order, are Hairday, Moonday, Twoday, Weddingday, Theday, Fryday, Standday, and Fabday.
Edit 3: (Man, I am thinking way too much about this) When we calculate the information for a desired date, we also have to take into account the time zones! Those will change the UNIX TimeStamps for the formula. When people enter their desired dates in your form, I think it assumes GMT, as Glitch's formula does.
@Lord Bacon-o: Ha! Technically, I was born Hairday the 17th of Junuary, Year -149; my next birthday will be Theday the 48th of Bruise, Year 15. Seeing my actual birthday like that makes me feel old. Year -149? Yikes!
I came in on the tail-end of Alpha, but my Glitch's birthday (according to that awesome script) is, most likely (given my understanding of corresponding timezones to GMT): 1:00AM, on Moonday the 24th of Fever, Year 12.