[It][1] is visible here, try to clear your browser cache and see [this question][2] for various other explanations.
explanations. Rendering seems to be slow at the moment according to the [renderd queue length][3], so be patient when adding new data.
Also please check the name of the buildings you added, I doubt the numbers are their official names. If you want to add addresses, use the [addr][3] [addr][4] key. If these numbers are just some reference, use the [ref][4] [ref][5] key instead.
[1]: http://www.openstreetmap.org/?lat=40.807721&lon=-74.390218&zoom=18&layers=M
[2]: https://help.openstreetmap.org/questions/102/i-have-made-edits-but-they-dont-show-up-on-the-map
[3]: http://munin.openstreetmap.org/openstreetmap/yevaud.openstreetmap/index.html#renderd
[4]: http://wiki.openstreetmap.org/wiki/Key:addr
[4]: [5]: http://wiki.openstreetmap.org/wiki/Key:ref