Microsoft Studios president Phil Spencer has told Official Xbox Magazine UK that Halo is Xbox's "most important IP".
Referring to Forward Unto Dawn, the web miniseries released to mark Halo 4's launch, he said the show had "something like 70 million views".
He continued:
"I think it helped us with the launch of Halo 4. But it also was just a thing people liked to watch. I think it helped growing what IP is capable of and getting people to understand the stories and characters.
"I also think going into the launch of any game, it's a nice tie-in; we learned that with Forward Unto Dawn where you can get people upbeat and excited about the IP and bring it as part of your overall launch momentum."
Regarding the Halo TV series, which will be produced by Steven Spielberg, Spencer commented:
"I definitely don't think of it as filler. Halo, you could argue, is the most important entertainment IP that Microsoft owns.
"I can't use the word filler anywhere near Halo, it just won't work. If we're going to do a television series with Halo, we're going to do it the right way, and we're going to do it because we think it really matters."
The next entry in the Halo series is set for release later this year but does not yet have an official title.