It doesn't surprise me that some folks have no trouble with updates, and some have so many problems they lose faith in all technology. My 70 with hard drive choked on the update it downloaded itself, but when I side-loaded the updated I downloaded from Archos.com it worked fine, and every app I've tried works fine. It connects using 802.11n with my d-link router, hasn't crashed once, and in general seems peppier.
I suggest you re-download the update and try again. If WiFi seems to not work, delete your setting and try to set it up again. Perhaps do an android reset anyway, as that will switch the swap ram to 64mb.