I've just installed Ubuntu 9.10 and fired up Firefox, what I have noticed is that the Internet is slower than it is with the other machines that I have with identical connection.
In particular, it takes it a long time for it to look up a server. Once downloading has begun, the speeds are normal, but it is very very laggy prior to starting the download: Firefox's status bar reports
Looking up <server>... for up to 15 seconds, where it would usually just flicker for a fraction of a second.
Any ideas on what could be causing this and suggested fixes?