Sure, multiplatform is good. But money and services earn exclusivity. I would love to have it all on my PC. Past E3 I'll be torn on what to consider investing in, I'm only really considering a 3DS at this point (mostly thanks to Monster Hunter, Shin Megami Tensei and a few first party titles so far) but I'm sure there will be other systems that will try to wow me with exclusives past that. More than one most likely (I'll probably want the next 3D Mario they'll be unveiling for Wii U for one, unless they try something different and fail at making it a must have, similar to Sunshine, who knows what Sony and MS will do).
Honestly I'd be glad if Nintendo stopped trying in the home console market, providing a handheld hybrid (3DS 2 with higher resolution, the return of book mode, twin sliders, 4 shoulder buttons and multi touch, with HDMI out and Wii U style GamePads for local multiplayer/TV play), Sony stopped trying in the handheld market and only provided a home console (PS5 or also a handheld hybrid, Vita 2 with HDMI out and DualShocks for local multiplayer/TV play), and Microsoft just stuck with a PC spec (supporting and having publishers target it for x number of years, providing them in small, tablet, or whatever form they want and offering the same optional live and cloud services). All their offerings on far less hardware, competition for time and money still there in a different form, and not amongst their own self each on top, win win for me. Their recent troubles in the respective markets could enable the viability of this scenario (at least for two of the three companies) making it more than my selfish wish, unless they somehow turn things around or come up with something more disruptive and successful for the next gen.