Yep, it does.

Personally, I'd wait... Initially, the Prelude and GW-8 didn't have ANY style editing tools. Now they have almost the same functionality as the G70 (albeit without detail drumkit modification and the amazing ease of the touchscreen system), and some improvements, even. I wouldn't be surprised to see the style assembly included in the future, given how they appear to be importing whole chunks of the E/G series code...

Main thing is, IF it happens, if you had already bought your Prelude, you wouldn't have to sell it to get the new features. Unlike if you had a Yamaha, for instance

I'd wait, rather than get an E50, if I were you... Alternatively, you could get a Sonic Cell and convert the Prelude styles to Yamaha format, and play it through the SC via MIDI...