Personally I would feel cheated by a PS4.5. I bought my PS4 ahead of time mainly because I liked the price point and the games offered. The thing is that up until now the only game I own that absolutely requires a PS4 is The Order (which I could easily live without). Had I known about a PS4.5, I might have held off on my purchase (depending on price and release date).
If it does exist, there's two scenarios. First one, it's marginally stronger and there won't any PS4.5 exclusive in which case it's useless (I really don't care about 30 vs 60 fps and all that pixel counting stuff). Second scenario is that it's a significant boost in power and that some games (or maybe just some features in games) will be exclusive to it, in which case I'll be furious that I got fooled into buying a console that can't play all the generation has to offer.
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