I think if you want a significant increase, don't shell out tons of money on a laptop and get a nice desktop instead. They're far cheaper and more upgradable, not to mention cooling won't be a problem.
To answer your question, i7's are simply a smarter chip than C2D's. Are they faster? depends on what you're doing. The absense of FSB allows i7's to clock themselves faster when needed, on the fly; so theoretically if your cooling is sufficient, it should provide a pretty significant boost over a C2D.
To answer your question, i7's are simply a smarter chip than C2D's. Are they faster? depends on what you're doing. The absense of FSB allows i7's to clock themselves faster when needed, on the fly; so theoretically if your cooling is sufficient, it should provide a pretty significant boost over a C2D.