Title says it all.
MP3 for lossy and FLAC for lossless is the perfect combo. Be awesome if we could make Albums for both!
Edit: Ok, now this is interesting. I decided to toy around with the idea, so I took a couple of FLAC tracks and renamed them as MP3s (wouldn't play that way) so I could put them into an Album with MiO. Naturally it didn't play either, until I renamed the Album to .FLAC! It played! However, it would only recognize and play the first track, so not exactly a win here. Still, it hints that there might be a way to do this, maybe by just adding "FLAC" as a recognized extension for the Album Maker?