Will .PNGs with alpha display correctly on a webpage?

I want a tiling background with a shadow overlay. I don't know where the shadow will wind up (fluid layout) so I can't bake them into the background.

Can I use a .PNG with an alpha channel?

If the browser supports it, yes. IE is really the only one that has issues with it these days, though I've heard they've fixed it in IE8. I haven't tested it out myself, yet, though.

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