Having owned every rimfire cartridge except for the 5mm...
I still prefer the 22lr for most things. The benefits a numerous....
You can range from ~300fps (and quieter that a pellet gun) to just under 1,800fps for blazing fast performance. Accuracy *can* be as good as 1moa to 100yds, with the rifle rifle and ammo. It is extremely versitile, and has a specific type of ammunition for any and every use.
If familiarize yourself with it's trajectory, and know your ammo and rifle well, it is a 80+yd gun for the average cottontail or prairie dog (wind permitting), and is more than enough gun to take a racoon size critter within reasonable distance (under 50yds, IMHO).
However, the WMR will extend your range (assumine you find an accurate rifle/cartridge) and allow you to take larger animals. It is on the VERY bottom of the spectrum for the average coyote, but will work with a well placed shot within a reasonable distance (inside 75yds, IMHO). It makes a great bobcat rifle as well, with minimal hide damage.
The long and short...my 22lr's get at least 10x as much action at the range and in the field, but for an avid small game hunter...the 22mag needs to be in collection. Especially with the release of the newer 2,200fps+ Vmax and TNT rounds (assuming you find a rifle that shoots them well).
I will never be without a bolt action 22lr and a bolt action 22mag.
I would mind getting rid of my 17's, though they would be a ton of fun if I had ground squirrels or prairie dogs in my neck of the woods.
With the re-release of several 5mm rifles for 2009...I think you'll find a lot of used 22mags on the market. That cartridge is kind supreme and a hoot to shoot...why it ever went dead, I'll never understand!