It isn't. Maybe I was just being a little impatient. but I would wait for a LONG time, like 30 minutes or something, and it would still be loading the same thing, the little bars in the loading bar not changing, like it froze up.
The wierd thing is when I load a TF2 map in Gmod it doesn't take a long time, but when I load a map on TF2 it freezes(or takes an UNBEARABLY long amount of time.)