Should I repot my seemingly happy orchid?

[missxashlee]

I inherited a white phalaenopsis orchid from someone at work who believed it to be "dead". I know better, so I took it home. All blooms had wilted and fell, so I clipped the spike back just a bit.
It's been a week since I've had it at home and I noticed new root growth as well as a new arm growing from the spike. All seems well, however I'm concerned with the potting media and pot. Pot is solid glass, no drainage/air flow. I'm almost certain there is that green stuff inside the pot that florists stick cut flowers in for an arrangement. Around the roots is a mossy type of stuff. This all prevents me from seeing the roots.
I visited a respectable nursery today and inquired on repotting. I was advised to wait since the orchid seems to be flourishing.
I know orchids need airflow and drainage, though!! What to do...