I left a comment under the theme release about this but as it's not appeared I can only assume it's not been received. So here goes again:

I installed 3.5.2 today and my blog's CPU usage jumped above 37% and its memory usage above 5% (I think it hit 11% at one point). I tried the theme on a few more servers and they all showed massive CPU and memory usage. Everything returned to normal once I reverted to version 3.5.1. My question is, has this issue been fixed in version 3.5.3?

Call me fussy but I don't want to be responsible for my clients having their server accounts suspended. Until I know the bug has been fixed I will advise my clients to stick with version 3.5.1; which is a shame because Atahualpa is a great alternative to Suffusion - one has square looks, the other has rounded looks.

How are you measuring memory usage?

All sites I tested it on used servers provided by Hostgator. Their HG theme provides a refreshable CPU and Memory usage meter. I used that meter, with several refreshes, to check CPU and memory usage. Plus I looked at the running processors. On each occasion the process with the highest usage was index.php (WordPress). That process was not a lone runner - for some reason the theme prevented plugins from quitting or the high CPU usage prevented them from quitting. I can't recall which plugins it interfered with but I believe they were different ones at different times.

The only reason I noticed the problem is that one of the tested sites had its CPU usage so high that it was unable to load (Received the Apache server error that's usually accompanies the suspension of WordPress's index.php).

There was a bug in 3.5.2 that caused problems with earlier versions of WP and I only had it installed on one site for a couple of days with no issues. I would be curious to hear if 3.5.3 does the same thing your 3.5.2 installs on your Hostgator sites.

All sites were WP 3 MS. I'll try 3.5.3 later today and post the result here.

please install the WP-Memory-Usage plugin and look at the usage in the dashboard with both versions