OK. the next step may be to rebuild things directly depending on libxcb. It may be a version thing. Note that fixing things like this becomes alot easier if you use one of the port management tools: I think I wold recommend portmaster , although portupgrade is more mature. Both of them allow you to do things like 'portupgrade -r [portname] to upgrade everything dependent on the port with one command, and several hours <g>. Install your choice, and check theman page for the syntax. Both products man pages have comprehensive examples.
More usefull info after a bit of searching: It is a version error: libxcb is now version 2, and installs libxcb.so.2. As a hack, sometimes softlinking the missing library entry to the existing one functions (ln -s /usr/local/lib/libxcb.so.2 /usr/local/lib/libxcb.so.1), but it is not a fix - merely a short-term workaround until you have fixed the problem.
from what I can see, though, a proper clean, deinstall and reinstall of libxcb should fix it - the problem is between two parts of the libxcb port.
Code:
cd /usr/ports/x11/libxcb
make clean
make build deinstall reinstall
Should fix it.