If you are a Plus subscriber, you’ve been give 150MB of space to keep a copy of your game saves. Up to 1000 saves can be kept in this manner – meaning almost everyone will have more than enough space.
The only glitch will be for those games that have copy protection on the game save. You can still upload the saves, but you won’t be able to access them for 24 hours once you do.
PlayStation Plus just gets better and better in terms of value. Each month there’s free games (and while individual months might not appeal to you, on balance you’ll be getting plenty to play with), and there are a number of other little perks built in.