According to videogaming247 the PC version of GTA IV is to be shown at Games Convention in Leipzig. Given the location and PC focus of the event it's hardly surprising, but this is the first time it's been confirmed by any source.

VG247 has learnt from a source close to Rockstar that the PC version of GTA IV will be shown behind closed doors at Games Convention next week.

No clue on specifically what’s to be shown, but expect the first pieces to pop up after the show.

GC’s looking quite hot this year, innit?

Link: videogaming247 - GTA IV PC to be shown to press at Games Convention