Sure,
just remember that gdb comes out from porting issues and for its particular
structure is slow.

IDA Debugger is great and presents the advantage of plugin integraton,
this thing is really important because allow you to harden debugger from
hostile code ;)

thanks ahmadmansoor ! :)

ollydbg is good, and easier to learn, but will become less useful as more people move to x64, i for one have already installed Windows 7 x64 version on my laptop, it will be my only OS (apart from VM) from now on...

IDA + Ollydbg
Olly for a "fast" debugging
IDA for a deeper work
Using together, however, is the best (example generate file .map with IDA and then pass the .map file to Olly and continue works on the same target).

IDA for static analysis

Debuggers
Windows
Olly for Ring 3 Apps
Softice/Windbg for Ring 0 code
Immunity Debugger (olly+python) for quick exploit writing

*nix
gdb + a nice gdbinit script
IDA Debugger (remote ) + gdbserver [ this is quite nice actually]
kgdb for Linux kernel debug

Speaking of a GDB init file, mammon's gdbinit is pure jewel.

http://www.802.11mercenary.net/~johnycsh/misc/mammon-gdbinit-fixed.txt

Ollydbg - Daily use
IDA Pro - Full analysis
Syser Kernel Debugger - Hard job

WinDbg is good for remote debbugging

olly64
 

Ne1 hear of plans for an olly x64? asked on olly.de but no answer...

tnx

Olly wasn't and will not be designed for 64bits, as discussed on the official support forum (woodmann's).
However it works for 32bits applications running on 64bits OS.

For a newbie, Windbg or Visual Studio are probably easier to use,
but once you understand the basics and want more, switch to Olly. It's probably not too user-friendly, but it's too much powerful!