It's better to have it and not need it than need it and not have it. Keep the 7D.
I'm all for that saying although in this case I see a limit to it. Because if this saying were 100% true we should all own multiple 1Dx bodies for backup on the field and some at home. In this case, the OP wants to venture into video work. There were many issues for me with my 7D for video use in the past that caused me to sell it and buy 3 60Ds eventually. What people hardly factor in to video work is size and weight for support systems. Lighter is ALWAYS better in regards to DSLR video support systems, especially if you're in the exploration stage. You'll save more money than just the transition between 7D and 60D, you'll also save on the accessories in the future. The 60D is still a more perfect video body at this point than the 7D. Why? It's the lightest and most versatile body with natively adjustable kelvin, ISO 1/3 increments, and easier aperture dialing which you can't get from the lightest weight xxxd cameras without magic lantern. Another thing about magic lantern, is that the 60D is the only body that makes full use of every ML feature. The 7D is still in alpha... You'll have to wait quite awhile before the port is finished. The 60D works great NOW. The swivel screen is very useful for video and there's no problem getting another viewfinder like zacuto's zfinder on it for video. Like other says in this thread, audio is very important. The 60D's soundboard is also still the most adaptable and if you're planning to plug a zoom h4n, rode mics, lavaliers, etc into it you'll have no issues. I know this because I shot video with three 60Ds for over a year with many different support and audio systems. The 7D tends to have issues up to now even with the latest firmware, especially with the alpha ML on it as one of my colleagues ended up trashing ML and had to go blind with no audio monitor for the rest of the event. Not cool. I'm not saying that the 7D is incapable of doing good video, but you'll sure as hell have a much easier time on the 60D. It's really the best budget cinema camera out there. Now if you're a photographer all the way, different story, keep the 7D if so. But I'd still rather have two 60Ds than one 7D for video any day.