I think if you fly from FL to Vietnam one or two times a year, that should be the deciding factor. As that alone would propel you to the dizzy heights of Skyteam Elite or even Elite Plus

Look at it this way. If your next big trip to Vietnam is before VN joins Skyteam - which one little birdie told me we could expect in December 2009 or Jan 2010 - you won't be able to credit it to your new favorite FFP, right? So just stick with whichever program you use - VN (or Asia Miles).

But... if it's after the big day, all the other programs will have published their earning on VN metal by then. As you know which booking classes VN lowest fares book into on your regular long hauls, it'll be pretty easy to weed out programs that don't give you full miles for that. (You will have to ask nicely someone who's a member of OK+ to check this for you as one now needs to be logged in with their account details on their website to see the earning ratios )

So just wait and see till VN actually join and all the earning rates are published. Then do your research and come back with the schemes you have in mind - it'll be much easier to decide.