I made the mistake of opting for x86-64 Gentoo for one of my desktop boxes ("upgrading" it to 32bit this weekend), meaning I have to use the 32bit precompiled OpenOffice binaries. But these need hooking into a 32bit JRE which x86-64 Gentoo doesn't have, since making 32bit apps available through Portage is seemingly something that Gentoo Won't Do Because You Should Be Happy With 64bit. So whenever you start OOo it spends about a minute looking for a JVM (and failing) before you can do anything. I could have manually installed Sun's 32bit JRE, but I can't be bothered.
Disable Java in the options and it starts in 1-2 seconds on the same machine.
By way of comparison, I tried the same trick on my 32bit box (similar spec but with slower HDD's) and OOo was as snappy as hell and opened like the proverbial soil off a shovel.
If there's any functionality I miss through disabling Java, I haven't encountered any yet. And please note I'm not saying that Java is slow to execute (it isn't), it's just appallingly slow to load.
I use OpenOffice at work, mostly as a viewer for documents others send around in Microsoft Office formats. As such, I doubt I'm going to run into the limitations of OpenOffice when Java is disabled. The speedup is amazing: from 5-6 seconds on my 1GB, 3.4 GHz notebook to almost instantaneous. I like Java as a programming environment, but Sun absolutely has to figure out how to cut down the JRE startup time, at least for embedded applications.
