Passenger journeys on the National Rail network increased by 6.7% during 2006 to a sixty year high of 1.147bn , according to the Association of Train Operating Companies (link below.)
http://www.rmtbristol.org.uk/2007/02/growth_in_passenger_journeys_b.html#more

This is the highest number of passenger journeys ever made on the post-Beeching rail network , which is now around half the size it was in 1946.

According to ATOC , around 3.2m journeys are made on the railway network every day. Passenger journeys have increased by more than 50% since 1995/6. Significant increases in passenger journeys have been experienced across the whole country with headline figures including :

A 9.7% rise on long distance services (71% increase since 1995/6)
A 6.0% rise on London and south east services (48% since 1995/6)
A 7.3% rise on regional services (52% increase since 1995/6)

Quote :

"There is a huge programme of work in hand aimed at meeting rising demand - some projects are already underway and others are at an advanced stage of planning between government and the industry, ready for approval. The new High Speed 1 rail link to France is virtually complete and will handle domestic traffic from Kent in 2009. The Thameslink Programme has received Parliamentary approval and if it gets the final go ahead will massively expand capacity into London from both the north and the south. Crossrail, currently before Parliament, will address traffic east and west of London as well as through traffic."

But despite railway spending being at a record high , few projects to increase capacity have been sanctioned by the government with recent franchise agreements concentrating on squeezing more out of the existing network , rather than investing in infrastructure. The Thameslink and Crossrail projects have yet to secure funding and will take more than three years to implement even if they secure funding this summer.