Yes, and it will be.

There were 60 questions tagged signature when I started. When my edits go through, there should be 1. digital-signature and email-signature together fit 47 of them (some already had the relevant more-specific tag); code-signing fit 6, hashing fit 1, user-agent fit 1, and I'm not sure what to do with the following 2.

These ones are about using handwritten signatures in digital documents:

• How can I add a signature field in a PDF? (not a digital signature)
• How can I sign a PDF document quickly and cheaply?

This one is about using a static image (an “image signature”) as a form of signature analoguous to a handwritten signature:

• About the security of adding a signature to a PDF file

_{^{The network has rejected my retagging-only edit to the remaining question for some odd reason.}}

Maybe. There has been no community consensus as of this revision of this answer; thus there should not have been any mass-retagging (not yet, anyway).

That said, there are currently 4 questions tagged signature (down from 60). They are as follows:

Two about using handwritten signatures in digital documents:

• How can I add a signature field in a PDF? (not a digital signature)
• How can I sign a PDF document quickly and cheaply?

One about using a static image (an “image signature”) as a form of signature analoguous to a handwritten signature:

• About the security of adding a signature to a PDF file

One about the on-filesystem location of signature-related configuration for Microsoft Outlook:

• Outlook, Config file for users and signatures

Yes. It should, and I'm on it. On a completely unrelated note, the edit queue is currently full.

There were 60 questions tagged signature when I started. When my edits go through, there should be 13. digital-signature and email-signature fit 41 of them (some already had the relevant more-specific tag); code-signing fit 3, hashing fit 1, and I'm not sure what to do with the following 2.

This one is about using handwritten signatures in digital documents:

• How can I add a signature field in a PDF? (not a digital signature)

This one is about using a static image (an “image signature”) as a form of signature analoguous to a handwritten signature:

• About the security of adding a signature to a PDF file

Yes, and it will be.

There were 60 questions tagged signature when I started. When my edits go through, there should be 1. digital-signature and email-signature together fit 47 of them (some already had the relevant more-specific tag); code-signing fit 6, hashing fit 1, user-agent fit 1, and I'm not sure what to do with the following 2.

These ones are about using handwritten signatures in digital documents:

• How can I add a signature field in a PDF? (not a digital signature)
• How can I sign a PDF document quickly and cheaply?

This one is about using a static image (an “image signature”) as a form of signature analoguous to a handwritten signature:

• About the security of adding a signature to a PDF file

_{^{The network has rejected my retagging-only edit to the remaining question for some odd reason.}}