I've got a HP dv6540el with ipw3945.
I always boot with kill switch on (wireless off) but this is my experience:

- boot:
Sep 21 00:13:10 HPdv6540el kernel: [   17.116000] ipw3945: Intel(R) PRO/Wireless 3945 Network Connection driver for Linux, 1.2.2mp.ubuntu1
Sep 21 00:13:10 HPdv6540el kernel: [   17.116000] ipw3945: Copyright(c) 2003-2006 Intel Corporation
Sep 21 00:13:10 HPdv6540el kernel: [   17.120000] ipw3945: Detected Intel PRO/Wireless 3945ABG Network Connection
Sep 21 00:13:10 HPdv6540el kernel: [   19.008000] ipw3945: Radio Frequency Kill Switch is On:
Sep 21 00:13:10 HPdv6540el kernel: [   19.008000] Kill switch must be turned off for wireless networking to work.

- nm after boot show only wired connection (in context menu)

- activating wireless (moving switch to off):
Sep 21 00:21:38 HPdv6540el kernel: [  528.420000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
Sep 21 00:21:39 HPdv6540el kernel: [  528.632000] ADDRCONF(NETDEV_UP): eth1: link is not ready

- now nm show also wireless connection, according to iwconfig
          Mode:Managed  Frequency=nan kHz  Access Point: Not-Associated   
          Bit Rate:0 kb/s   Tx-Power:16 dBm   
          Retry limit:15   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality:0  Signal level:0  Noise level:0
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

$ uname -a
Linux HPdv6540el 2.6.22-11-generic #1 SMP Mon Sep 17 03:45:58 GMT 2007 i686 GNU/Linux

$ lspci
00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 0c)
00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 0c)
00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 0c)
00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Contoller #4 (rev 03)
00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 03)
00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03)
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)
00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03)
00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 03)
00:1c.5 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 6 (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03)
00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03)
00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3)
00:1f.0 ISA bridge: Intel Corporation 82801HEM (ICH8M) LPC Interface Controller (rev 03)
00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 03)
00:1f.2 SATA controller: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA AHCI Controller (rev 03)
00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 03)
02:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG Network Connection (rev 02)
06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E PCI Express Fast Ethernet controller (rev 01)
07:09.0 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller (rev 05)
07:09.1 Generic system peripheral [0805]: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 22)
07:09.2 System peripheral: Ricoh Co Ltd R5C843 MMC Host Controller (rev 12)
07:09.3 System peripheral: Ricoh Co Ltd R5C592 Memory Stick Bus Host Adapter (rev 12)
07:09.4 System peripheral: Ricoh Co Ltd xD-Picture Card Controller (rev 12)