How exactly is this a "con?" It's called an opinion.
First off, the taskbar in Windows 7 is *NOT* trying to accomplish the same thing as Mac OS X's Dock. They have different design philosophies... the taskbar has always been about window management and the Dock has always been about application launching.
Secondly, you're telling me that a little tiny white dot on the Mac OS X Dock is somehow easier to see than a large square that fills in with color on the mouseover on Window 7's taskbar? I get that obviously everyone sees screen widgets differently, but seriously, unless you're very blind, it's not hard at all to see which applications are actually running on the Windows 7 taskbar.
Also, "no drag/drop rearrange?" Have you used Windows 7 at all, or have you just claimed to? You didn't realize you just click and hold on the application icon and move it anywhere you want to on the taskbar, just like you can with the Mac OS X Dock? Did you not realize that you can drag/drop application icons directly from the Desktop and/or Start menu onto the taskbar? Have you never right-clicked on icons and seen the "pin to taskbar" option?
Seriously, did you really use Windows 7 at all?
I guess I'm just spoiled with Snow Leopard. \
Okay, please give me a list of free plugins for Windows XP that will replicate the numerous new technologies and features that are in both Windows Vista and Windows 7. Specificially, show me free XP plugins that replicate Instant Search, BitLocker, UAC, the new kernel version, the hardware-accelerated GPU Aero desktop and sandboxed 64-bit IE8.
Also, you claim that no one will want to upgrade to Windows 7 when they cost over $100 (a half-truth), yet all the Apple worshipers here seem perfectly content having paid $129 for every single Mac OS X upgrade between 10.2 and 10.5.