This is a little self serving (I run the company that offers this service) but I came across this old post and have been mooching around geekzone as a result and have come to the conclusion I should hang out here more often.
In answer to the question though. You can now get instant TXT alerts to the grabaseat deals from Travelcafe. I've been 'eating my own dog food' and have scored a couple of $1 fares in the last week (using the service myself) so I know it works.
http://www.travelcafe.co.nz/index.php/Get-TXT-Alerts-to-grabaseat-deals.html
The TXT alert service is proving to be pretty popular but I'd be really interested in some geek feedback. What would make it better?
As you can tell I haven't spent much on UI design for it (i haven't spent anything on design in fact) and if anyone can recommend a local UI designer for this sort of thing (and a few other similar projects in the pipeline) I'd be grateful.
Cheers,