DX mentioned this to me earlier today. In one month the price will increase for PS+ by $10 per year. Not a huge increase, but it'll now be $59.99 starting September 22 2016:
On a side note, I ordered a year's subscription from this site for $37.99 on sale:
$42.99 - $5.00 using promo code THANKYOU.
I found the deal on slickdeals:
I haven't gotten my code emailed to me yet, but the company updated their front page a few hours ago saying it could take a couple days for them to send out the codes because they're getting so many orders in. With the price increase I doubt it'll get much cheaper than this since even last black friday it was only on sale for $39.99.