I've registered on both sites.  Given up on dollarrewardz for now, since I couldn't seem to figure out how to get paid directly in bitcoin.  tasks4dollars looks more promising, but seems to be fussy about which country I log in from, which is a problem for me.  I guess I'll have to stick to coinworker for the time being, but I'll keep an eye on these sites to see  if anything changes, as I'd be interested to try them out properly if it does.  Best of luck with the sites.