I'm new to Sublime Text 2, and I love it. I look forward to seeing this product evolve because I think it's a great foundation for an incredible product.
As far as usability is concerned, there are some UI differences from other IDEs that are cool, and some that are a little funky. Specific to Find and Find In Files, I feel like this is an area that can be improved. I'm having consistent problems with Find in local files and I'm getting to the point where I don't trust it anymore. I'm not sure exactly what I'm doing that's wrong, but I often get into a state where Find isn't finding results that I know exist in the file. Sometimes this gets resolved by clicking around in the file, and hitting CTL-F again. Again, I'm not sure exactly what I'm doing to create these situations.
I recently discovered the "Find In Selection" button, which has been the culprit when nothing is selected. To me, this button should do nothing when there is no selection. In this case, the button should either auto turn off, or Find should function normally... not sure if everyone would agree with that, but it's weird when Find does nothing when the match is directly below your cursor and nothing is selected.
Also, Find In Files can be improved... For example, I can't find anything that toggles whether or not to search subfolders. Sometimes I just want to search a folder... and sometimes I want to search my entire project. I think it always searches subfolders, but I'm not sure. There's also no progress indicator, so I have no idea how long the process is going to take, and when it's completed.
Just some thoughts...