I have some clients with WP and lost of page views ( 100 K a day ). On a dedicated XP 3400 with ! gig mem, it just froze ( never crashed as such ... ).
I switched one of them to a virtual account ( yes, those awfull virtual account that are always down according to Pro

) on a dual xeon 3.0GHZ. I just had to upgrade the mem to 4 gigs, and it is puring like a well fed pussy ....
He uses about 2 Mbps , so roughly 350 gigs month....
So , get CPU and mostly memory . And you should consider co-location so you can upgrade those features on the cheap side.
Now, let the flaming begin ....


He is in Europe, so it is 3:00 am there : a new day
PHP Code:
VISITS
Total 11,057,067
Average Per Day 82,215
Average Visit Length 0:34
Last Hour 2,433
Today 6,891
This Week 575,506
PAGE VIEWS
Total 16,014,547
Average Per Day 111,125
Average Per Visit 1.4
Last Hour 3,529
Today 9,711
This Week 777,874