Same here. Networking is seriously screwed up in beta 6. I've never had any problems with networking in previous betas. Of all the betas, 5 was the best. 6 is definitely a step backward.
If it helps, here's the output of ifconfig:
	Code:
	
[mike: mike]$ ifconfig -a
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
        inet6 ::1 prefixlen 128 
        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1 
        inet 127.0.0.1 netmask 0xff000000 
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        ether 00:16:cb:89:5a:03 
        media: autoselect status: inactive
        supported media: autoselect 10baseT/UTP <half-duplex> 10baseT/UTP <full-duplex> 10baseT/UTP <full-duplex,hw-loopback> 10baseT/UTP <full-duplex,flow-control> 100baseTX <half-duplex> 100baseTX <full-duplex> 100baseTX <full-duplex,hw-loopback> 100baseTX <full-duplex,flow-control> 1000baseT <full-duplex> 1000baseT <full-duplex,hw-loopback> 1000baseT <full-duplex,flow-control> none
en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        inet 192.168.0.104 netmask 0xffffff00 broadcast 192.168.0.255
        ether 00:16:cb:04:f3:8c 
        media: autoselect status: active
        supported media: autoselect
wlt1: flags=41<UP,RUNNING> mtu 1500
en2: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
        inet6 fe80::201:23ff:fe45:6789%en2 prefixlen 64 scopeid 0x7 
        inet 10.37.129.2 netmask 0xffffff00 broadcast 10.37.129.255
        ether 00:01:23:45:67:89 
        media: autoselect status: active
        supported media: autoselect
fw0: flags=8822<BROADCAST,SMART,SIMPLEX,MULTICAST> mtu 494
        lladdr 00:16:cb:ff:fe:55:71:40 
        media: autoselect <full-duplex> status: inactive
        supported media: autoselect <full-duplex>