Yep, very similar. But then, one could say in the same way that the Karma Sutra and the Bible are very similar because they both teach you how to be happy in your sexual life.
In reality, the Christian is using the rosary to focus his thoughts while addressing the throne room of the Universe, and the Bhuddist is using the beads to engage in a mental exercise.
The rosary isn't in the bible but an instrument of prayer accepted by the RCC. That's not what I was told about buddhist prayer beads. Many buddhists have told me they are praying to God when they are using their prayer beads. I guess it's the same when some Catholics go on autopilot when saying the rosary. I don't pray the rosary unless I can focus otherwise it's just another 'mental exercise'.