If someone can confirm what I believe...
A key pair created last decade was 1024 bit. I created a subkey recently of 4096 bit. However the pub key is still 1024 bit. Do I need to export my 4096 bit subkey, and use gpg2 --key-gen with 4096 bits, then import the subkey to be secure (yes/no)?

I don't like littering the Internet with gpg keys, but I am thinking that is my only option to be more secure.

Thanks

partial output:
gpg --edit-key 12345678
pub 1024D/12345678 usage: SCA
sub 1024g/ABCDEDFG revoked usage: E
sub 4096R/1A2B3C4D usage: E

From public key server:
pub 1024D/12345678

sig sig3 12345678

sub 1024g/ABCDEDFG
sig sbind 12345678
sig revok 12345678

sub 4096R/1A2B3C4D
sig sbind 12345678

Keys are always created in pairs, so the old public key would not be able to be used in conjunction with the new private key.

Revoke the old key and generate a new key. Remember that a different key is used for encrypting than for decrypting.

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4096 is a bit of over kill ( except for the NEEDED!!! useage )

the nsa is using 2048 for almost all things

I would recommend at least 2048-bit, and I think that's the usual recommendation nowadays.

However, realistically, this is rather a "theoretical" vulnerability. Unless you are trying to defend against a government or a very determined attacker, 1024 bits are probably fine. Of more concern should be the overall infrastructure of key-management: how are the private keys being secured? Who's in the position to steal a key, and how likely is it that she might do so, and how likely is it that she might get caught? How is the issuing (and periodic replacement) of public keys being taken care of? What is the sensitivity of the data that is being secured, and how and where is that data being transmitted?

Someone who seriously wants to get their hands on a key is probably not going to "break" it. Instead, they'll probably just either try to steal the thing, or, ugh, to break you.

Agreed, personally I think SSL solutions are needed, but over rated and misunderstood. In most instances, SSL only encrypts data between two endpoints so that they can not be sniffed on the network. Most applications using SSL are storing the data decrypted. It is easier for a real hacker to break into a system than to break the SSL itself.

These days 2048 is the default. You can use a subkey with 4096 bits. And use the subkey for all signature and asymmetric crypto.

There are actually two separate keys one for encryption/decryption and one for signing as well. If you use the same one for both, the key will become vulnerable to attack.