Google: We've decided to take site speed into account in our search rankings



i know that drupal becomes terrible on speed after a certain # of modules. not too sure about wordpress - haven't needed to build a full out content site for a while. i just create a static layout with a php file for content - since i go paid traffic most of the time. duno how you seo guys deal with it.
 
The effect is relative to speed of your competitors + the magnitute of the effect shouldn't be very high. I'd say just make your sites fast enough for users and you'll be fine.
 
From that link:

"While site speed is a new signal, it doesn't carry as much weight as the [ame="http://www.youtube.com/watch?v=muSIzHurn4U"]relevance of a page[/ame]. Currently, fewer than 1% of search queries are affected by the site speed signal in our implementation and the signal for site speed only applies for visitors searching in English on Google.com at this point. We launched this change a few weeks back after rigorous testing. If you haven't seen much change to your site rankings, then this site speed change possibly did not impact your site."
 
I use this for speed:

usp_labs_jack3d_new__68875.jpg
 
It only affects 1% of queries and it is hard to tell if this has an effect on me, as they say this did not create much change in SERPs anyway.