Question: Yes, I am aware one is a framework and the other a CMS.

However, I am a one man team that develops projects/websites for myself and I have a limited amount of time to get these projects off the ground, so speed is crucial.

Basically I am looking for the easiest and fastest method for creating web apps without being limited on features.

Would it be best/fastest to learn Codeigniter or to build off of Wordpress and develop my own themes/plugins? Possibly another option that would be more viable?

I deal a lot with video/photo media and high traffic websites.

Thanks!

Answer: 
I would suggest using CodeIgniter. The logic is simple, and it doesn't really have limitations, unlike WordPress. WordPress is designed for blogs, and if you are looking for flexibility, I would go with CodeIgniter.

CodeIgniter has one of the best documentation available as well. <http://codeigniter.com/user_guide/index.html>

If you are looking to learn CodeIgniter, NetTuts has some great tutorials, with different levels.
<http://net.tutsplus.com/articles/news/codeigniter-from-scratch-day-1/>

There are some nifty CodeIgniter libraries that can get you head start on your projects:

* <https://github.com/benedmunds/CodeIgniter-Ion-Auth> - Ion Auth, CodeIgniter Authentication Library
* <http://www.kaydoo.co.uk/projects/backendpro> - Backend Pro, designed to build admin side of your application.

If you are looking for CodeIgniter based blog/CMS, I would also suggest PyroCMS, one of the best I've used.
<http://pyrocms.com/>

CodeIgniter also has a great image manipulation library built in, so you won't have to learn too much about generic PHP image libraries.
<http://codeigniter.com/user_guide/libraries/image_lib.html>
I agree with tpae. Definitely WP is not meant to be used for web apps. So forget about it.

CI is great, easy to learn, and in combo with [Backbone.js](http://documentcloud.github.com/backbone/) and Phil's [REST\_Controller](http://philsturgeon.co.uk/blog/2011/03/video-set-up-a-rest-api-with-codeigniter) it's a beauty to work with :) You'll be building highly responsive web apps in no time (this sounds like a commercial :D )