Through February 8, 2016, you can purchase Hilton points with an 80% bonus. This means you are ultimately purchasing points for .56 cents per point and you are maxed out at buying 80,000 points (which equals 144,000 with the bonus) per account per calendar year).
While a bonus is always great, I personally wouldn’t buy points through this promotion unless you have a specific hotel in mind. I personally value Hilton points at less than .56 cents per point, so buying points for more than I think they are worth is not great in my mind. With that being said, there are definitely some opportunities where buying points is much better then paying the lowest rate at the hotel.
For example, category 1 hotels cost just 5,000 points per night. By purchasing points this means you are only paying $28/night. While I haven’t gone through every category 1 hotel to check the rate, most properties are way more then $28/night. And remember, if you have Hilton status, you’ll get the 5th night free bringing the cost per night down slightly.
Overall… this could be worthwhile for certain situations, but I wouldn’t suggest purchasing points speculatively.