Market Press with Upfront vs. legacy themes

Hi,

I'm cleaning up my themes and updating client sites. Is Market Press integrated into Upfront or should I still be offering the MarketPress themes (FrameMarket, GridMarket, Product, etc.)?

Also, are the legacy themes Nelo, Dixi, Triden, Business Portfolio, Business Feature, Business Services, Sleekphoto, etc. still supported and for how long?

I have clients that like and are using these themes. Is it time to find them another theme? Not everyone wants Upfront for everything (although a great theme!)

Thanks!
Chuck S.