Well, I have FCPX now, and I'm trying to make it flexible to my projects. I'm a 9 years Vegas user, so the transition has been interesting. The audio interface is a tad confusing so far, for example.

What addons do you guys and gals use that really helps in your projects. I've googled some, but would rather get some direction from my friends here.

Thanks in advance.

Event Manger X
it manages your Events and Projects, and you can hide the ones you don't want to load up, with one click.

7toX
if you want to load in FCP 7 projects into FCPX. There is also one from X to 7.

SliceX
an advanced masking program that you can use for different effects, and use in combination with the built in color correction tools to have (more) advanced color correction and other things, like selective blur etc.
You can also buy a version with the Mocha Tracker built in.

Callouts
from Ripple Training. It does one thing very specific: making 'callouts' animations onto your video. If you have a use for this, it is fantastic.

Natress Curves
Curves for Color Correction. Seperate Luma Curva also in the package.

mLogo
package from MotionVFX (he has great Motion5 Templates too) that also does one thing: it has presets for logo animation. If you have use for it, it's great, if you don't, ignore it ;-)

Since you mention Nattress Curves and RippleTraining Callouts, look at NoiseIndustries. They have a slew of plugins that are inexpensive, useful, use their FXFactory system. Nattress is part of that. You don't need to purchase their system to use the free base and purchase individual plugins such as Curves.

Noise Industries - Visual effects for Final Cut Pro, Motion, After Effects and Premiere Pro (http://www.noiseindustries.com)

As they note, many of their plugins work in After Effects as well.

Yes we are using the FXfactory plugin structure. I think a couple of those plugins is only available trough FXfactory.

Tokyo Pipinator is also one we use, but again it does something very specific. I have very good words about Simon's service though, he is the creator of that plugin.

FCPEffects.com

Good stuff.