I sometimes pull up GM Forum on my iPhone, and it works pretty well. For some reason, I have to click on Search three times before I can type in the box, but that'* the only issue I have with it on my phone.
Still, as a Web developer, I know it can be optimized to make better use of the small screen. I plugged "vBulletin iPhone" into Google, and this theme was the first result
. There was also Forum Runner
, which uses a server-side plugin and a client app ($1.99).
I saw in the other thread that Venom'* short list isn't (and understandably so), but this may be one thing to consider penciling in at the end.