I stumbled upon the following topic ( where The behavior of Client not registering PTR record by default is modified prior to Windows7 (mostly during Vista time) and is the intended behavior.
The DHCP server will use this information, along with its dynamic update configuration, to determine whether or not the DHCP server will perform the PTR record update against the authoritative DNS server on behalf of the client, or if the client will perform the PTR update against the authoritative DNS server on its own. The first step of this process still involves the client machine sending an SOA-type query to the configured DNS server.
The client then receives information from the authoritative DNS server indicating which server will be processing the update.
Update [27/06/2013]: new information regarding the topic: Windows 7 & Reverse Lookup DNS Registration [Update] In my current project we have an Active Directory domain where we use Windows DNS servers with domain integrated DNS zones.
For the reverse lookup zones we configured secure only updates.
The record appeared in the reverse DNS zone as expected. I do think you can use the GPO if you want to fine-tune the registration behavior as it contains 3 options. I haven’t found a way to do this by GPO, I might have missed it though.