@ElizaBennett - My understanding is that vasectomy is a less invasive procedure with a shorter recovery time than tubal ligation. It makes sense if you think about where the surgeon is working - even minor abdominal surgery is no picnic.
I looked it up, and the failure rate is about the same for both. But vasectomy is done in a doctor's office with local anesthesia and takes about ten minutes. Tubal ligation is also a short surgery, but it requires spinal or general anesthesia and there is a greater risk of complications.
I've learned all about it because my wife and I are grappling with the same decision - except she's voting for a third child and I am *not.* I'm trying to sweeten the deal by saying that I will get a vasectomy now, but if she insists on a third child, the offer is withdrawn. (I'm only half-serious, of course.)