Svchost.exe memory issues in Windows 7?

I'm using Windows 7 Ultimate x86 on a home-built Phenom II X4 with 4GB of RAM, and my memory usage is steady at about 40%. In Task Manager, svchost.exe is using upward of 90-100K of memory. I've looked around and it turns out this was a widespread problem in XP, and Microsoft had a fix for it, but I'm not sure if it would be a good idea to try and use an XP fix. What is going on and what should I do?