Some of us got blown away by twitter, some of us just got annoyed that it didnt work with Google Talk for Google Apps. But surely it should work right?
For GTalk to talk with Twitter you only need to add/invite twitter@twitter.com to your Google Talk contacts. It will instantly accept the invitation and you're only your way. It’s that simple. However that's only if you're signing in using a Gmail account (e.g. yourmailadd@gmail.com).
If you're a user of Google Apps and use Google Talk with that account, then simply adding/inviting twitter@twitter.com will get you nowhere. At least that’s where I got.
So, why didn’t it work?
When I checked the "Service Settings" for chat in the Google Apps Domain Control panel, it was obvious; to IM outside the Google network, you will need to edit your Service (SRV) records in domain settings. Ah, so that’s why!
The support document from Google said I'd need to enter the following DNS entries.
_xmpp-server._tcp.yourDomainName.com. IN SRV 5 0 5269 xmpp-server.l.google.com.
_xmpp-server._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server1.l.google.com.
_xmpp-server._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server2.l.google.com.
_xmpp-server._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server3.l.google.com.
_xmpp-server._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server4.l.google.com.
_jabber._tcp.yourDomainName.com. IN SRV 5 0 5269 xmpp-server.l.google.com.
_jabber._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server1.l.google.com.
_jabber._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server2.l.google.com.
_jabber._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server3.l.google.com.
_jabber._tcp.yourDomainName.com. IN SRV 20 0 5269 xmpp-server4.l.google.com.
Something was still not right; the invite to twitter@twitter.com was not getting accepted; even after leaving plenty of time for DNS entries to propagate.
It was time to try out another IM client. Google supports the jabber/XMPP protocol. This means I should be able to use any other IM client that supports the jabber/XMPP protocols.
I choose Pidgin because it had a useful debug window! So I installed Pidgen and configured it to connect to Google Talk for my domain as instructed, and tried to sign in.

Now I'm getting somewhere! I was still missing some more DNS entries. _xmpp-client._tcp.kavinda.net could not be found. After a quick nslookup to see the entries for _xmpp-client._tcp.gmail.com

I added similar entries for my domain kavinda.net.
_xmpp-client._tcp.yourDomainName.com. IN SRV 5 0 5222 talk.l.google.com.
_xmpp-client._tcp.yourDomainName.com. IN SRV 20 0 5222 talk1.l.google.com.
_xmpp-client._tcp.yourDomainName.com. IN SRV 20 0 5222 talk2.l.google.com.
_xmpp-client._tcp.yourDomainName.com. IN SRV 20 0 5222 talk3.l.google.com.
_xmpp-client._tcp.yourDomainName.com. IN SRV 20 0 5222 talk4.l.google.com.
In goDaddy domain control pannel you'd enter the record,
_xmpp-client._tcp.kavinda.net. IN SRV 5 0 5222 talk.l.google.com.
like:

That did the trick, I was able to sign into Pidgen. Now Back to Google Talk; Signed in using my Google Apps account, added twitter@twitter.com and it was accepted instantly. I had arrived.