Linux-USB
The Linux-USB mailing list is a very active mailing list pertaining to all aspects of USB and Linux. Here one will find the most recent patches for the USB code in the Linux kernel. There is also good discussion on support of digital cameras from time to time. Overall a great list to peek at every week or so.
To subscribe to this list send a blank email to linux-usb-subscribe@suse.com. A confirmation email that must be replied to will then be sent back. Either send a reply to the email address in the reply-to: section of the email, or the address listed in the confirmation message itself. To unsubscribe from the list send a blank email to linux-usb-unsubscribe@suse.com. This action will then have to be confirmed with the same method used for confirming subscription to the mailing list. For a list of other useful commands send an email to linux-usb-info@suse.com.
Linux-kernel
The linux-kernel mailing list is a very high traffic mailing list detailing all aspects of the Linux kernel. This list is only for those who wish to have more information than the Linux-USB list and the gPhoto-Kodak lists contain. However, it covers much more of a broad spectrum of topics than Kodak digital camera support under Linux.
Before posting or subscribing to the Linux-kernel mailing list is is highly suggested reading the Linux-kernel mailing list FAQ. It could save much time and embarrassment. It also contains useful information on who certain individuals are in the Linux community in relation to their standing on the list.
To subscribe to the list (remember, it is about 200 emails a day) send an email to majordomo@vger.rutgers.edu with "subscribe linux-kernel username@mailserver" in the body of the message where username is the email account to be used and mailserver is the name of the mail server. Remember to omit the quotation marks.
An alternative to joining the list would be to get the list in digest format. This is a better format to many as it is a few emails a day rather than several hundred. One drawback of this is that it is not as easy to discuss the issues with the mailing list as most mail clients don't know how to deal with the digest in its format besides dealing with it like plain text. To subscribe to the digest send an email to majordomo@vger.rutgers.edu with the line "subscribe linux-kernel-digest username@mailserver" in the body of the message. Where username is the email account username to be used and mailserver is the name of the mail server. Remember to omit the quotation marks.
Unsubscribing from the mail list is as easy as subscribing. Just send an email to majordomo@vger.rutgers.edu with the line "unsubscribe linux-kernel" in the body of the message, or alternately "unsubscribe linux-kernel-digest" if subscribed to the digest. And again, remember to omit the quotation marks.
Rather than subscribing to this list it would be highly suggested to search through the archive which is accessible via the URL listed above. Another alternative is the Kernel Trafficsite. It contains a good overview of the weeks kernel developmental works and discussions in a summary format.