Most multisig is now accomplished with P2SH.
As long as you are using compressed keys and using P2SH for your multisig, I believe Bitcoin 0.9 supports as "standard" up to 1-of-12, 2-of-10, 3-of-8 or 4-of-6 (due to a limitation of 500 bytes).
If on the other hand you are using the outdated OP_CHECKMUTISIG, then I think you are limited to a maximum 'y' of 3, and 'x' cannot exceed 'y'.
Yes - I think that currently you can't do more than 2 out of 3 and still be a standard tx (and I have no idea when if ever that might change).
Are you sure about that? For some reason I though 3-of-3 was supported.
Also, as I pointed out you can exceed x-of-3 and still be "standard" as long as you use P2SH.
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If they are still non-standard when they will be standard?
Because larger multisig combinations can be accomplished with P2SH, I don't think there is any plan to increase the scope of OP_CHECKMULTISIG. I think the plan is to encourage multisig users to use P2SH transactions instead, and increase the size of the standard P2SH script.
The last I heard, they were looking into allowing "standard" P2SH multisig up to 15-of-15 for Bitcoin 0.10