awesome =D
Some interesting additions to the original... fever trip! xD
I was kind of looking forward to more evolutionary concepts, though, like differentiation of the viruses within a stage (so that you could work to keep the ones you like alive, instead of blindly infecting everything with everything). That would also solve the difficulty complain from some people regarding the 'spawn x amount of viruses' levels, since your viruses will get stronger the more time you spend on a level due to the natural elimination of the weak. It also gives alternative approaches to endless mode (cultivating a few super-viruses vs. mass-producing weaker ones).
Also, we need the ability to turn auto-infect on/off. It actually makes things harder in survival stages (because one must now avoid red blood cells in addition to the white to prevent unintended infections)