I mostly surf, emails, Microsoft Office. I watch MLB TV occasionally which is Flash. Compared to my 2010 CD2 maybe it runs a little warmer. I have not compared Flash to the newer version of Flash which I downloaded last week. But I have read the new release Flash is much better then before.
95% of the time my fans are 2,000 RPM. I do not consider this a warm or hot laptop so I am not looking for stats.
I use Safari, AD Block, Click to Flash. I think this trio helps with battery life and heat.
There are so many mixed reviews on heat with the i5 & i7. For me I bought the i5 with 128 because it is more then enough processing power for me and the price was $1199. I think it comes down to how much you really need and how much do you want to spend. I would not put heat in to the factor, that is something you will have to judge yourself with your usage.