I wasn't going to vote at first considering I wasn't around for most of 2008 and haven't seen or am able to give a valid opinion on most of the categories. However considering the organization tells me there are some nasty ties in several of the listed categories I've decided to give my opinion on the things I do think I'm qualified to say something about.

Best JCS'er:
I would've voted for EvilMike but that's a pretty biased opinion since I haven't seen a good deal of the work of most other people on this list so I'm gonna leave this one blank.

Best CTF level:
Starlit Summit by Ragnarok. All levels on this list are very good actually but I specifically liked Starlit Summit for it's sheer size, visual style and the few innovative ideas it has. Like EvilMike said, this is also a good level for JDC.

Best Battle level:
Enter the Chaos by FireSworD. I admit this is a bit of an unfair vote considering I haven't seen ALL the levels on this list but Enter the Chaos is just such an awesome level that I doubt any of them would've deserved the vote THAT much more to actually make voting for this invalid.

Best Non CTF/Battle level:
Tempted to vote for Pearl-Shell Shore here considering it's a great level. Sadly it's also the only level out of this list I actually saw so this is also gonna be blank.

Best MP Pack:
Also blank. Out of these packs I've only checked out the CTF levels so far, so it's impossible to give a decent opinion here.

Best SP Pack:
Tomb Rabbit 2 beta by Kejero. Honestly I only played Mike's pack and TR2, but TR2 is just so overwhelmingly amazing that I very much doubt any of the other packs on this list would beat it (and the opinions I've heard from other people reinforce this notion).

Best Tileset/Conversion:
Fortress of Forgotten Souls by Blade. I'm actually working on a level with this set and to be honest I must say that after using it it's not all that's cracked up to be: it's very hard to use and the more I try the less seems possible. Still it's a fantastic looking tileset that can really produce some very nice visuals with it if you use it correctly. More importantly in my opinion it just blows all other nominees out of the water so it gets my vote all the same in the end.

Best improved JCS'er:
Also blank. I've barely seen any of the levels produced by any of the authors of this list so I can't even begin to imagine who qualifies for this.