In this article, I am going to touch on the certificate part. I realize there are quite a lot of changes for Exchange Certification in terms of generate requests and import from Exchange Cmdlet point of view.
Here is the comparison between the same command on both Exchange 2007 and Exchange 2010 RC.

Exchange 2007

Generate request

New-ExchangeCertificate -GenerateRequest -Path c:\yourdomain.req -KeySize 2048 -SubjectName "c=SG, s=SG, l=SG, o=My Pte Ltd, ou=Exchange, cn=yourdomain.com" -DomainName yourdomain.com, autodiscover.yourdomain.com, mail.yourdomain.com, cas001.yourdomain.com.local, cas001, cas002.yourdomain.com.local, cas002 -PrivateKeyExportable $True

Import Certficate and Enable services

Import-ExchangeCertificate -Path C:\yourdomain.cer | Enable-ExchangeCertificate -Services "IIS,POP,IMAP"

For .pfx format

Import-ExchangeCertificate -Path c:\exported_cert.pfx -Password:(Get-Credential).password

Exchange 2010

Generate request

New-ExchangeCertificate -GenerateRequest -KeySize 2048 -SubjectName "c=SG, s=SG, l=SG, o=My Pte Ltd, ou=Exchange, cn=yourdomain.com" -DomainName yourdomain.com, cas01, cas01.yourdomain.com.local, cas02, emstapch02.yourdomain.com.local, mail.yourdomain.com, autodiscover.yourdomain.com -PrivateKeyExportable $True

Notice the missing parameter of "Path"?
This is how Exchange 2010 do if you need to generate physical file on your CAS server

$Data=New-ExchangeCertificate -GenerateRequest -KeySize 2048 -SubjectName "c=SG, s=SG, l=SG, o=My Pte Ltd, ou=Exchange, cn=yourdomain.com" -DomainName yourdomain.com, cas01, cas01.yourdomain.com.local, cas02, emstapch02.yourdomain.com.local, mail.yourdomain.com, autodiscover.yourdomain.com -PrivateKeyExportable $True
Set-Content -path "C:\req.req" -Value $Data

Import Certficate and Enable services

Import-ExchangeCertificate -FileData ([Byte[]]$(Get-Content -Path c:\portal.cer -Encoding byte -ReadCount 0)) | Enable-ExchangeCertificate -Services "IIS,POP,IMAP"

For .pfx format

Import-ExchangeCertificate -FileData ([Byte[]]$(Get-Content -Path c:\certificates\ExportedCert.pfx -Encoding byte -ReadCount 0)) -Password:(Get-Credential).password| Enable-ExchangeCertificate -Services "IIS,POP,IMAP"

You may notice the drastic changes on the import portion. The import command required additional input such as file encoding format.
Well, the "get-help" command is very useful with "-example" appended behind.
Have fun with Exchange 2010!!

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