Well, my coins have finally been transferred. Last night I submitted another help request through the Poloniex support site. Instead of being polite in my request as I had been previously, I wrote them a fairly belligerent message explaining that I would be posting warnings about them on social media and the BBB. Within a few hours my coins had been transferred.
I am happy to have the transfer completed, but disappointed that it came to the point where I had to make threats to get things resolved. I do believe that Poloniex is trying to be a legitimate exchange, but until they prove that they can handle the current volume of trades I will be staying well away.
*I wanted to edit this post and add a small note. I noticed a few minutes ago that the Poloniex support ticket I created last night was closed and listed as 'Resolved'. I find this interesting for a couple of reasons: When I initially created a ticket a few weeks ago the response I got was something like 'We are experiencing issues, we don't know whats wrong, wait longer' (that ticket remained open). Then in the response I received today they stated something about certain wallets experiencing issues with transfers etc. The reason I find this interesting is that my coins showed up almost immediately after the message I received today, which showed my ticket as resolved. Unless they knew the exact issue, and knew that whatever they did on their end had sent my coins they would not close my ticket, and list it as resolved. Based on these facts it certainly appears to me that they have the power to correct these pending transfers when they want to, and are either intentionally delaying them or selectively addressing tickets.