You can really access orkut from mobile now by going to m.orkut.com. No need to use our old days methods anymore.
The mobile orkut is centered around individuals. It supports profiles, scrapbooks, search, friend-lists, birthday reminders, friends updates, pending friend requests, etc.
Group features, those related to communities are completely omitted. Also you can not edit your profile from mobile.
You can still access communities on mobile to by switching to www.orkut.com, i.e. web-version. Of course, it will be slower.
The only thins surprised me is silent launch by Google. I am still confused if Orkut blog is just meant for reviewing OpenSocial Apps for orkut. In past also they did not bother to post about prominent features they launched or upgraded.
Thanks Darnell for discovery and credits!
Update: Official announcement on Orkut blog (April 17, 2008)