The specifications for S/MIME v2 have been released as informational RFCs.
The new documents are:
S/MIME Version 2 Message Specification (RFC 2311)
S/MIME Version 2 Certificate Handling (RFC 2312)
PKCS #1: RSA Encryption Version 1.5 (RFC 2313)
PKCS #10: Certification Request Syntax Version 1.5 (RFC 2314)
PKCS #7: Cryptographic Message Syntax Version 1.5 (RFC 2315)
All documents can be found at <http://www.imc.org/smime-pgpmime.html>.
Work to make standards-track S/MIME v3 continues, of course. :-)
--Paul Hoffman, Director
--Internet Mail Consortium