Just can't help but think it may be too little too late for Apple. They started out fine with their first two Apple TV streamers as it gave us a hobby to play around with. Even though they were locked down being able to jailbreak and install XBMC made it a non issue.
Now we see Roku pretty much dominating the streamer market, because rather than restricting their device they opened it up to channel developers. With over a 1000 channels available, and more released almost every day they are quickly becoming the industry standard when it comes to media streamers. Check out this impressive list and compare it to what is available for Apple TV.
So even if we could buy an Apple Television with a built in ATV streamer at what will be undoubtedly be a hefty price, why would we want to limit ourselves. As quickly as technology changes this is just one more piece that may quickly become obsolete while the TV portion continues to function fine. Remember when TVs had stereos and record players built in? That fell out of favor quickly.
It seems like a step backwards and in my humble opinion Apple would be better off investing in shrinking the AppleTV the way Roku did so it could be the size of a USB stick and plug directly into a HDMI port. Out of site and easily upgradable. There is no question Apple hardware and UI are great, just open up the Apple TV to developers already and start competing on content.
Its FAR from too late. Maybe it dominates the geek market. Small box streamers have almost no market penetration among normal people who have cable, and their cable provider box/dvr.