Tomato flowers fertilize themselves, so you might not get anything different. I don't worry about cross pollinations with my tomatoes, and saved the seeds of 4 different kinds to plant this year.I have different 6 tomato varieties planted together in a 5'x7' bed. I might save some seeds to plant next year and see what kind of weirdness happens. LOL
Not to say it can't happen. Just not as likely as other plants.