OK, nuts and bolts first: I tried this on 3 different computers, one desktop running Linux Mint 10 64bit, AMD Athlon 64 X2, another desktop with Mint 10 32bit, AMD Athlon 64 (single core), and an 8 year old Dell Inspiron 5100 laptop with Ubuntu 10 10, Intel ???.
On all three machines, I tested Deluge 1.3.2 and 1.3.3.
The way I found the problem originally was this: while downloading, on the Deluge menu bar, I clicked "Help", then clicked "Home". CPU ramped up to 100%. Closed the browser that it opened, no change...had to close Deluge. Restarted Deluge, all is calm, CPU running at 10% +/-. Then, thinking the browser triggered this, I opened Firefox while Deluge was running normally. No change to CPU other than starting FF. Surfed a little bit, no issues. Then tried it with Chrome...no trouble. Went back to Deluge Help menu, clicked "Community", WHAM! 100% CPU. I also changed default browsers to see if one or the other was the cause when clicking on the Help links, and it still went to 100% with both Firefox and Chrome. Next, I tried it all over again, this time without an active torrent download, and it still occurs.
So, it seems the web links in the Help menu are triggering this problem. It happened for me on all three machines with 1.3.2 and 1.3.3.
Now, my user solution is that I just don't click those links again. (Don't need to anymore...I know where you're at.

I like Deluge a lot. Compared to all other choices for Linux, this one is the best! So, I don't know if this info has been helpful or not, but if I missed something that you might want to know, let me know and I can hopefully post some answers.