No matter how fast your computer is there is a slight delay between asking an application to open and it actually being opened. Depending on the size of the application and how well it was built, this time may vary. I have a still top-of-the-line 15" unibody Macbook Pro and even small applications take a few moments to open fully.
A feature that I’d really love to see (and if there is a way to do this that I do not know about please put it in the comments) is to open an application in the background. For example, I might be writing a post in my WordPress admin in Chromium and realize that I have to open Skype for my morning meeting. So, being the avid Spotlight user that I am, I key in CMD Space, type in Skype, hit Enter. Never in the world of computing has it been easier to open an application. As the focus falls back from Spotlight to Chromium I can resume typing my post. Which is great. But then Skype rears its rather ugly head and takes focus from Chromium even though I’m typing in it.
This has been the way computer operating systems have always worked (as far back as I can remember). But why not give me some way to open applications in the background? We know that there will always be some slight delay between me asking the application to launch and its interface being available so why not plan for that?