I've been doing burpees since August 2007 (3-4 times a week, 1 week break every 2 months). I started with 10 descending sets (1-2 minute rests). After 2-3 months, I was up to 20 descending sets (1-2 minute rests).
Every time I did my 20 sets it was painful and grueling, but I stuck with it for about a month until I realized I should rewind and start over at 10 and patiently add a set each month. My body was not ready for it. I would rather be set back a bit than just quit all together.
10 descending sets was a little too easy for me so I added an extra pushup (2 pushup burpees without the jump, 30 second rests in between sets). 9 months later and I'm still doing them...now 4-5 times a week. I'm only at 13 descending sets, but why rush. I'll be at 30 in no time.
Only advice I can give is that you have to be motivated and disciplined to do them. Many times I've come close to giving up because it does get boring and repetitive. I've packed on alot of muscle and lost about 10-15 pounds of body fat within these 9 months. There's no easy way around them. You just have to get up and do them.