Extraordinary claims require extraordinary evidence. If we had the experience of other people plus some other evidence, then that might be enough. The alien example given earlier was quite apt. I believe the existence of aliens to be possible, even probable, but I doubt the testimony of people who claim to have seen one, or been abducted by them.
Additionally, there are other, plausible explanations for God experiences. Often, these experiences happen to people who already believe in God. These experiences, then, could just be self-fullfilling prophecies: something which would ordinarily be given an alternate explanation is given the God explanation since you believe that God exists and does things like this.
The God hypothesis is very prevalent in society, so naturally, our minds might tend in that direction. If garden gnomes were just as prevalent a hypothesis, then more people would probably be claiming to have experiences with garden gnomes.
Lastly, humans don't like not knowing things. It's much easier to say "This experience was God" rather than to admit "Hey, that was really weird and I have no idea what just happened." We tend to personify things, because that makes them more familiar, more comfortable to us.
Due to these various explanations and the extraordinary nature of the claim, the experience of other people alone is not enough to convince me of the existence of God.