Hi HenryS,
Just to clarify... there is actually an official position on the matter. No need to speculate on how to get a supported version of Java. When Sun owned Java, Apple worked to with Sun to build their own port of Java to install on OS X. Sun was acquired by Oracle. Oracle now owns Java. Apple has worked with Oracle to transition the effort of porting Java on OS X back to Oracle. Oracle now does this today... Apple declared that after Java 6, they would no longer produce their own port.
Apple does not intend to provide another version of Java (provided by Apple) for OS X -- not unless they change their mind. That's now Oracle's role. And please note... the two companies actually did work TOGETHER to make this happen (it's not a competitive thing.)
If you want the latest version(s) of Java, with fixes, security patches, etc. then the only way to get that is by downloding it from Java.com.
Once you install Java on your Mac, you will find that it STILL will not work in most web browsers (including in Safari). Again... that's by design (it's frustrating, I agree). You still have to go into preferences and enable.
You can go into Safari prefences -> Security -> Allow plug-ins -> Manage website settings -> pick Java (Java 7 update 51 which is current as of the time I am writing this), and there's a setting that asks what you want to do when a website wants to run Java (ask/block/allow/always-allow, etc.) and you have to configure this.
If in "ask" mode it will remember our decision on a site-by-site basis.
One more thing...
When Java applications or applets run, they can actually specify which version of Java is required to run that program. Many Java programs don't care. Some use specific nuance features and do care. It is possible to install say, Java 6, and then end up running across a program that refuses to run unless it has Java 7. The reverse can also be true... having Java 7 installed by having an older program which isn't compatible and wants Java 6.
On my Macs today, I _only_ hava Java 7 installed and there is no Java 6. Everything I need works. But when Java 7 was still fairly new, I did have both and needed both.