Right now, when you transfer UR points to JetBlue, you get a 25% bonus, so the effective ratio is 1:1.25. JetBlue points are similar to Southwest points in that their value is basically tied to the cash price. You can generally get about 1.25 cpp when redeeming for flights. If you have a JetBlue credit card, you’ll also get a 10% rebate, which makes it a bit better. This promo runs through November 30, and you should see it after logging into your account.
As a side note, AMEX only gets to 1:1 even after a 25% bonus, so Chase is still better here.