The USA captain has joined until the end of the season.
Moyes said: “He is a boost and we will be glad to see him. Hopefully he will get here in time to see the game.
“He might need to play up front for us at the moment because of our shortage of strikers and he can play off the sides as well.
"What it gives me is another body. I expect his fitness to be good, he has had the break now which he needs and I am hoping that we can get him into the football quite quickly.
“Everybody who knows him tells me he is a terrific athlete so that helps.”
“Clint Dempsey is now doing very well at Fulham.
“There are a lot of good players over there but the problem is the passport situation and the amount of caps they have, so Landon is probably thought of as the main US player so it will be interesting to see.
“It didn’t quite work for him in Germany, so that’s why we cant go over the top, we will have to assess him and see how he goes and see if he can help us and hopefully we can give him a platform to play on.
"He has been very positive and he is excited by it and looking forward to it. Tim Howard has filled him in on the details and this could work well for him, who knows it is difficult to say.
"People in America speak really highly of him as a footballer and what he can do so we hope to see that when he is here."