I have reason to believe that if columbus discovered the West side of the United States, that the West would have developed first. Also, it's very possible that we might be speaking Spanish instead of English. We would of had the Gold Rush sooner. What do you think?
It might have been interesting if the United States was developed the other way. I think it would have taken much longer. We might have been less developed until the technology was there. The east coast was much closer to Europe.
A more likely scenario would be that someone other than Columbus discovered America from the West, and development began there. Geographically speaking, it would have been exceptionally difficult for Columbus to reach the West Coast, as he would have been required to sail around Cape Horn. It would have been far easier for an Asian nation to cross the Pacific; in fact there is some argument that Zheng He, the Chinese admiral, did in fact land on the West Coast of the Americas prior to Columbus.
In any event, were the West Coast developed first, expansion across the continent would have occurred at a much slower pace, as the Rocky Mountains would have presented a formidable barrier. The Manifest Destiny of the U.S. would have been entirely different.
I think the only real difference might have been the way that people spread across the country. As it happened, the East was colonized first and people gradually began to spread West. I agree with pohnpei397 that the East would likely have still developed far more quickly because of its close proximity to Europe. There might have been colonists in the West sooner, but I doubt that would really cause huge changes. Consider also that Columbus was not the only explorer to discover America. It was named after the person who first recognized it for what it was, Amergo Vespucci (http://en.wikipedia.org/wiki/Amerigo_Vespucci). Europeans would have eventually colonized the East even without the aide of Columbus' discoveries.
I would be interested in knowing why you think that we would be speaking Spanish.
I don't think the west coast would have developed first. There would have been huge problems involved with getting colonists all the way to the West Coast. I think that other countries like England would still have decided to try to see what was on the east coast of the new continent. With that coast being closer to Europe, it would have developed first.
So I don't really think that there would have been a serious difference.