What if the X360 and PS3 launched at the same time?

[Mummelmann]

Like others pointed out; the price would've been very different and one also has to remember that the 360 probably, in part, got a fair deal of that number of sales from being the only next gen console on the market for an entire year. It had no competition in it's segment at all and that probably didn't hurt.
Then again, if both launched at the same time, the PS3's price would have seemed all the more atrocious so its hard to say for sure how it would have played out.
The way the PS3 came out a full year later (or actually more like 16 months later if you count ww launch and availability) people somehow assumed it was a lot more advanced that the 360 when it wasn't, this notion could have been killed in it's infancy if they launched simultaneously (you assume that a newer product is more advanced).
The 360 hardware failure rate would have been the same and that could have made the 360 look like a really, really unstable and shabby piece of hardware compared to the sturdier competitor.

So many factors here, we also have to take into account that Sony probably would've either cut features to make a cheaper console or even just launched at a lower price so as to be more competitive from the get-go. The price wars would also have started earlier but 3rd party support could have swayed more in one or the other console's favor (whichever one gained the best foothold in the market).

In my opinion this is one what if scenario that is impossible to imagine and I honestly have no idea how I think it would have turned out!