However, I am not sure it has made publishing poetry any easier. It is just another format for getting your work seen by others. Unfortunately, locating online magazines that publish the type of poetry you write takes almost as much work as locating print journals. The benefit of the Internet is that you don't have to pay to see a sample. The hardest task a poet has, besides writing the poem, is finding the right market for their poetry.
Diligence is the key to being published whether on the Internet or in print.
Also, from my experience, a good portion of Poet's Market readers are not connected to the Internet at home where they can easily search for potential markets. I think the Internet has, more than anything, increased the marketplace for poets. It has provided a number of poets and editors an inexpensive way to get their poetry and the poetry of others out into the community. Of course, the increased visibility of poetry in general through National Poetry Month and the Magnetic Poetry Kits you see everywhere has been a positive trend over the past few years. One thing that seems to be happening, that I am all for, is the opening up of poetry writing to the general public.