Can they be used in PRETTY MUCH the same way, for connecting bots?

Mostly. If a bot supports BNLS and allows you to set the BNLS server address, changing it to a JBLS will have the bot use that server and everything will work as it did when set to a BNLS address.

Yes; JBLS is a Java implementation of the BNLS protocol/service.

Is there like a list of what you could possibly need to use BNLS for? (As in, what you need to use BNLS for to get some values)

Only difference is JBLS can handle products that don't use a CD Key. Full BNLS packet documentation (including what the packets return) can be found on http://bnetdocs.com

Could anyone post, or link me to a simple guide (or snippet of code) which connects me to a JBLS/BNLS server and does BNLS_CDKEY or something in VB.NET or VB6?

Already did. BNetDocs gives you everything but a packet buffer/debuffer, and you can get that from my signature. Here's what you send, and here's what you receive.

But i'm not sure as to what I should use to connect to Battle.Net/BNLS in VB.

winsock

Well,  simplest way to do it in VB is to import the winsock object, add a winsock control to your form and do winsock1.connect "USWest.bettle.net", 6112

Is the System.Net.Sockets namespace the same thing?

Generally.