He won't be sacked this season quite simply because of how good all the other teams are. Even if I sold my soul to devil tonight, he wouldn't get sacked because it's his first season. The powers that be will let him buy players in the summer and if he's still shite at the end of next season, they will cut ties and call it a day.
The way I'm justifying it is:
Man A dates and marries a woman at the age of 21. The first few years are very hard, but after that he lives happily ever after.
Man B dates a new woman every few years, and I mean this guy is shagging some real hotties. But after 10 years, he's still messing around. After a while, will he still be able to find new woman after each experience?
I guess next season will determine whether Moyes finds that special woman within himself, or whether United has to turn into a bachelor.