There are snapshots available for MM:S that should work with the latest L4D2 update:
http://www.metamodsource.net/mmsdrop/1.8/
Please note that on Linux, the metamod loader has been renamed from server_linux.so to server.so to be consistent with Valve's renamings. So please change this in your metamod.vdf files or you can use the VDF creator on the MM:S site.
SourceMod will take a bit more time. It's completely broken on Linux at the moment but may or may not load on Windows. Hopefully we will have some snapshots for this tomorrow.
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