In short, it is a good thing, maximize your RRSP if you have the funds to do it. Also maximize your TFSA
RRSPs allow you to contribute now towards funding your retirement. Contributing to an RRSP has two main benefits: first, your contribution is tax deductible and second, your contributions grow tax sheltered inside your RRSP and as a result, they have the potential to grow at a much faster rate than funds saved outside an RRSP.
Long version (with all kinds of goodies):
Registered Retirement Savings Plan (RRSP)
http://www.rbcroyalbank.com/products/rrsp/index.html