Why push the alu so much? it will serve the OP no purpose other than to have him/her waste money,.....unless they are driven by aesthetics.
The whitebook is updated with the same NVidia graphics the alu macbook has the only difference(body aside) is the RAM being DDR3 in the alu and DDR2 in the whitebook....the OP will notice no difference with the tasks mentioned...all these peeps who go after form over function
DDR3 fsb all of it worth it. And yes you will notice a difference from the whitebook. My fiance has my 2.4 white book given with the x3100 card but still a huge leap into the aluminum
to the OP: in addition the screens on the new aluminum macbook are a huge leap forward for apple's introductory laptop line; they are amazing. The way the aluminum felt weight wise and in my hand sold it for me, and then I started them up side by side and compared the screens and hands down to the aluminums. 1249 student discount core price vs 949 whitebook core price for me... definitely worth the 300 for me and it sounds like we use same applications. Have your local applestore make an idvd project through an imovie export ~6minutes and you'll see the difference even with the new 9400m card in the old whitebook. (Yes same harddrive speeds too)