water coming out on my tailpipe. is that problem?

Nope it's totally normal. it's just condensation as the cold pipe warms up. You may notice it dripping out of your muffler as well. The muffler actually has a small weep hole to let the water out.

Normal, by product of the catalytic converter http://chemwiki.ucdavis.edu/Physical_Chemistry/Kinetics/Case_Studies%3A_Kinetics/Catalytic_Converters

I agree with both above,if you are not loosing coolant.

That's why they began making mufflers out of non-corrosive material ... if you let that water sit in the bottom of a regular steel muffler ... in 3 years your looking for a "Bull Dog Muffler Patch" to patch the rust hole