if some lines are too long, it will be forced to be newlined.
for example, normally a long line will looks like this
1 first line
2 this is the long
To move in vim in a natural way is possible.
What I did was, and I suggest you, to modify (or create) your "~/.vimrc" and add these two lines:
map g
map g
This will map you control-up and control-down to the movements commands (this is coherent with control-right and control-left to move around long lines)
If you add these other two lines, you can use the same command to move in insertmode:
imap g i
imap g i
(VIM is great !)
Greg Ruo