I wouldn't say that 2500 is normal, but then again, it may be normal to your fuel settings. If you have a lot of fuel running through the injectors, then yes, it's normal. If you have your fuel settings close to stock, then no, it's a high idle.
What RPM does your car idle when it's warm? Auto or standard? Is your narrowband O2 sensor good or is it old and caked up? Is your TB area clean? Do you have any air leaks? How long does your car take to lower its RPMs?
When I had my FIAV and ISC during the winter in Missouri, my car idled cold at or around Atown's numbers. As my original ISC and FIAV started to go bad, my idle jumped to 2k....in Hawaii! My idle went to 800-900 after removing the EGR, FIAV, vacuum lines, and ISC and has stayed there since. I'm not suggesting removing anything, just check for the normal turbo car items.
As you may know, DSMs are just funny that way sometimes, so you make the call.