In this case, I'd probalby prefer the AMD chip over the older T5 series. . .
I'm pretty sure that the T5800 is based off the newest release of Intel CPU's, it's just part of the budget chips. My GF's Gateway has the T5800 in it and it runs everything fine. Clock for clock, the Intel chip will beat the AMD chip.
Honestly, if performance isn't really an issue, I would go with whatever is cheaper. I know you said the difference was pretty negligible, but still.