No, they would be essentially indistinguishable as far as online video watching went, and just in general as well.
Now, the 15" has a Core i5 or i7 depending on the configuration, and that could very well make a difference in some areas. But if you're mainly looking for things like web browsing and youtube video watching, aside from the extra 2" of diagonal screen space on the 15", the three are going to be indistinguishable from one another.
Am looking to purchase a Macbook Pro -- probably 13 in. Can get either 2.4ghz or 2.6ghz for processor speed. (higher speed also comes with larger hard drive.)
Is there really that much difference between these two? And Is there a world of difference between either of those speeds and the 3.....ghz you can get on the 15 inch?
Would higher speed make viewing videos/listening to music online a better experience?
thanks for any help and info on other's experiences...
M

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