ns1.dynadot.com and ns2.dynadot.com have not been working for some time. Which caused all domains usign Dynadot dns to stop working. Includeing www.dynadot.com. May be you should put ns1 and ns2 in different locations so the do not go down together :)
I guess this will be a lesson to start looking for provider whose support is working 24x7 rather than "Monday - Sunday 9am - 6pm PST" and whose phone, when called, says "we are sorry; an application error has occured".
[This post has been edited by v_r_niles_us on Feb 19, 2012 9:33am.]