Will I be able to upgrade from 10.6.8 directly to Mavericks or install Mountain Lion first?

Question

I'm guessing no, but it would be nice to get official word Apple. I'd rather not deal with installing Mountain Lion unless I have to.

Answer 1

10.6.8 to 10.9 Upgrade Advice
There is a good chance one can directly go from 10.6.8 to 10.9 like occurred with 10.6.8 to 10.8, skipping OS X versions in the process. We don't know for sure until it's released, it makes logical sense though.
OS X versions 10.7+ do not run PPC based software your currently using Rosetta under 10.6
So you need to first check for compatibility of your third party software before any OS X upgrade.
If it won't run with 10.7 or 10.8, it likely won't with 10.9
http://roaringapps.com/apps:table
If your ok with your third party software requiring upgrades or replacements, then your good to go.
Next you will have to check the RAM and hardware requirements to make sure your machine is compatible with the upgraded OS X version, usually err a lot more than the minimal specifications Apple provides. Apple might provide the minimal hardware specifications, however it might not be ideal in performance, especially on nearly full boot hard drives.
I very HIGHLY recommend before one upgrades is to backup up their entire system using TimeMachine and/a bootable clone (ideal as you can easily revert) or TimeMachine + a copy of users files on a regular external drive then disconnect all drives before updating.
Have two copies of your data off the machine in case you need to do a erase and install of 10.9 to fix other issues with your machine. TimeMachine might have gotten corrupted unawares and refuse to restore and it would be on the older OS X version. So your extra copy of just users files on a regular drive or bootable clone is going to save your bacon.
Prevention is worth a ton of cure.  Most commonly used backup methods
Warning! If one connects a TimeMachine drive to a upgraded OS X system, because of the huge changes of the boot drive, it's likely going to cause a huge change to TimeMachine as it's a rotational backup system, it doesn't archive users files so older ones will be deleted.
If you have been storing older files on TimeMachine thinking you can restore them, then you need to make sure to save them off the TimeMachine drive on a external drive before upgrading OS X or making any substantial changes to your boot drive.
I also highly advise that if your machine has a boot hard drive (not a SSD), to reduce users files off the drive to bare minimal, they can be returned after upgrading. This has a effect of the new OS X version being written to faster portions of the boot drive instead of the slower ones with a full boot drive, also less defragmention occurs. Hopefully this will avoid a lot of the "I've upgraded and my machine is now slow problems"
If you have a SSD is to make sure you have about 75% of the SSD free space by reducing users files.
Regardless of a SSD or maximum RAM, after upgrading OS X on older machines it might appear slower than before, it's because newer OS X versions are more feature rich and tailored to newer machines with more RAM, faster processors and graphics capability. This is normal and to be expected for instance the OS X Lions really work better with 4GB of RAM or more, despite Apple saying 2GB is the minimal.
At this time we don't know exactly what minimal hardware will work best with the new OS X version or how to advise if certain machines are better off on the older OS X 10.6.8. However in my opinion it seems Early 2011 laptops and later with SSD's seem to go better with the newer OS X versions of 10.7 and later.
It doesn't mean yours won't work, it's just that it would be better with these later models than on earlier ones.
If your not computer savvy, there is nothing wrong in waiting until the problems of a new OS X upgrade be resolved before making your leap.
I also suggest one makes sure there are no other "problems" with their machine before upgrading as it very well come to light and leave you angry and confused on what to do.
Again, a ounce of prevention is worth a ton of cure. 
..Step by Step to fix your Mac
Why is my computer slow?
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