Is Google App Engine right for me?
If you are planning on a 'huge' website, then don't use App Engine. Simple as that. The App Engine is not built to deliver the next top 1000th website. 
Allow me to also ask what do you mean by 'huge', how many simultaneous users? Queries per second? DB load?
I am thinking about using Google App Engine.It is going to be a huge website. In that case, what is your piece of advice using Google App Engine. I heard GAE has restrictions like we cannot store images or files more than 1MB limit(they are going to change this from what I read in the GAE roadmap),query is limited to 1000 results, and I am also going to se web2py with GAE. So I would like to know your comments. 
Thanks