Is it too early? Only time will tell. The average speed of internet connections has been improving a lot every year. We have to assume that these consoles will be around for many many years, and lots of things will happen during that time.
In your view, what constitutes "too early" and "ready"? Is it the number of graphics-heavy gamers who also have an adequate internet connection reaching a tipping point for developers to target them? (and spend money)
Also, what are you imagining is the acceptable/reasonable requirements for latency to an XBL datacenter and sustained bandwidth for this to be feasible?