C.W.
My son was 2 years, 5 months when his little brother was born. He did the same thing and it was particularly tough because his dad left while I was still pregnant, so I had to deal with it on my own.
Here was what I did. I started "bedtime" a good 40 minutes before he needed to be asleep. We read a story together as a family and he "helped" me get his little brother ready for bed. Then, I helped him into his pj's. I told him that because he was the big brother, he was allowed to stay up later than a baby. He would lie on my bed and watch a dvd while I put the baby to bed (this is where the few extra minutes helped). Then, I'd go into my room to get him and bring him to his bed. I'd rub his back for exactly 5 minutes (he was often asleep by then). If he was still awake he got a kiss and I assured him that I would check on him again before I went to bed..after I cleaned up. (So, if he heard me moving around he didn't feel like he was missing anything.)
They each got their own one-on-one time with Mommy and we all got to bed at a reasonable time. He is now 6 and we have a very similar routine now too.
I hope this helps!
C.