Do you still need to recycle the application pool/ResetIIS in SharePoint 2010? Yep. This is actually setup for you by default, out of the box when you create a new web application in central administration. You can see this for yourself by doing the following:
Create a new web application
Be sure to create a new application pool:
Open IIS Manager
Select Application Pools:
Select the "SharePoint – 200" application pool
Right-click it, select "Advanced Settings":
In the "recycle" category, notice the "Specific Times" property:
Don't want it to recycle? Just remove the TimeSpan value and it will stay up forever, but be forewarned, out of the box memory leaks will eventually exhaust your SharePoint/web server memory!
Click the Ellipsis, click "Remove" for the timespan values
Click "OK", now your SharePoint Application Pool won't recycle!
You still need those handy warm up scripts running every 30 minutes to keep your environment running tip-top!