If you really like the E-30 (I do) and high ISO isn't a priority and you don't already have a stable of e system lenses, then a few more might be a good idea. I'd look for used ones as I'm reluctant to sink any more money in the e system...although I recently bought a 150 SHG and a 2x converter..both refurbs.
If Oly should bring out a new camera that will be effective with the e system lenses and of course it has the new sensor, then I think used prices will climb as there will be a demand again.
It just depends on your needs and pocket book. If you want cutting edge bodies, then for now at least Oly isn't the place to be...but that might change. If you want good lenses for your e 30 and you are satisfied with that camera, then now is a pretty good time to buy them.