So 1.5 is out...

[Bangraa]

....and I kinda derped and updated it on my comp.

Saved the bin files but it keeps downloading the 1.5 batch back in everytime I start.

I'll see you guys after it's patched!

[bren4q]

The minecraft.jar file from 1.4.7 is all you need.

If you can't get that manually, try one of the many tools out there that downgrade your version for you, like this one:
http://mvc.craften.de/

No install necessary. Just run it, select 1.4.7 from the Client list on the left, then click Change Version.

[Bangraa]

Thanks bren that did the trick (and whoops forgot about the 1.4.7 jar file @_@

[Krawkyz]

1.5 is great by the way. I hope we will be allowed to use /effect commands on ourselves