are xcf the same as psd?

being as I use gimp, when I save a layered image, i save it as an xcf file. I can save it as a psd file, however it does not recognize some layer modes, and will switch them back to normal upon saving - thus screwing up the signature.

So my question to all the ps users, if you download an xcf file, can you still open it with ps? And does it come out the way it's supposed to?

Nope if I am correct it doesnt, due to Gimp using different filters then PS, and thus PS wil not be able to read those, due to them not being compatible with PS, even if a xcf file is read-able, the layers that are using a filter that is only in gimp wil be 'trunkated' lets say, and thus useless for the Ps user...

The files are just not interchange-able...