Well I forgot something else. Let me throw another wrench at you guys. I forgot the brand new 2.4 would be online so no tax.
So: Open box 2.7ghz mbp 13" for around $1110 total
or Brand new 2.4ghz 13" for $1000.
When you first started this there was a 4% difference which was a great deal. But now, since the open box deal does not include Lion which adds another $30 the price difference is $140 or 14% higher the value is different. Personally, I would go for the new model for $1,000 and use the savings to upgrade ram or hard drive if needed. For what you do, as stated above, I don't think you will notice a tangible difference with a slightly faster CPU (both are very fast, faster than what I have in my 2010 15"). More ram will make it snappier if you have plenty of things open. Also, a faster, 7200 rpm hard drive will improve performance (faster read/write times like opening programs...) and you can use the original drive as a cloned backup. I think that is a better way to spend $140 - but that's me and how I think and make purchases.
Out of curiosity where is this $1000 MBP deal without tax? I know MicroCenter runs these deals but they are for pickup only so there is tax (in most states)