I think the majority of PS+ users rate the service solely on what free games we get, which is incredibly dumb. The free games aren't always appealing to me, but the discounts, automatic updates, cloud saves, and more make up for it.
I think the only time I've been disappointed in their selection of games is when they offer titles I've already bought for platform.
Beyond that, what are you paying for? Cloud saves clearly qualify as a service being provided for you. But paying an annual fee to qualify for discounts? That's a bit questionable as a primary motivating factor. Automatic updates should be a given for everyone given how awfully slow the PS3 updating is. If the betas they offered were truly betas, wouldn't they want as many people as possible to be playing it? I can't blame Sony for simply offering some additional bullet points to sell the service.
I have to say I've been really happy with the service ever since I've signed up simply for the cloud saves and "free" games alone.