Free OSX uprade?

I am still running OSX 10.7.5 and have only recently heard that there was a point where computers of a certain release date qualified for the update to 10.8. I am curious to see if I am still able to take advantage of that or if there was a deadline to meet. Also, I just read that there is another OS coming out so should I even worry about hitting 10.8 or should I just go straight to Maverick. Just for a side note, I am unable to connect to certain computers in our ftp at work because of a compatibility issue and I think the 10.8 update will fix it so I am still interested in getting the free dl if it is possible still just because it will solve some problems.