ss_teven has had some progress with SMS Plus recently, stating this:

We’ll, since I havn’t got a site up for this yet, i’ll post it here, so far, i’ve gotten sound working with Game Gear roms almost perfect, with a frameskip of only 4. Master System roms are still jumpy, but its getting there .

I’ve also added a few extra non emulation related features within, but it’d be upto you to try and find em Hopefully I will get a release out by Monday.

I’m trying to implement auto-frame skip, dunno if I will get it working by Monday or what.

I experimented with PAL support (for 50Hz tvs), and it sucks! Colours are all wrong, and it rolls, so i figure I’ve got the wrong values.

Anyways.. watch this space in the next few days for more updates… and hopefully a release

It all sounds great, and you can discuss the progress here