HS2's not a bad idea in principle, but I think the rail network needs improving elsewhere. As most of you know, I lived in Cornwall for 14 years, and when I took the train to London or Birmingham or wherever, it took ages. One of the most infamous stretches of line on this route is the line between Newton Abbot and Exeter which runs along the coast at Dawlish. It won't have escaped your attention that last year, storms forced the closure of the line due to the sea washing it away. It took several weeks to repair and re-open the line. 9 locomotives (plus carriages/freight wagons) and 18 multiple-unit trains were trapped west of Dawlish. Some were used to transport passengers across the limited network, and others had to be transported by road to other depots to be serviced and used elsewhere on the network.
Since then, there have been talks to plan for another line to be constructed somewhere in Devon so that if this happens again, trains will still be able to run down through Devon and Cornwall from the rest of the country. The preferred route at the moment is one going across the top of Dartmoor, using the Dartmoor Railway via Okehampton, then joining on at a new line at Tavistock, which would then head down to Bere Alston and join the main line again at Plymouth. This route seems sensible, but trains would have to reverse at Exeter St David's to head up to Okehampton and Tavistock, and then again at Plymouth to go into Cornwall - this would add a few minutes extra to the journey at each end, which would not be ideal. Other options include routes between Newton Abbot and Exeter which would avoid Dawlish, and I believe that one of these routes would be better - it wouldn't add much onto the journey, it'd probably be faster than the current Dawlish route, and express trains could be exclusively transferred to this new line through tunnels, meaning that the stations along the coast could be served by a more frequent local service. The exact route that this 'Dawlish Avoiding Line' could take is up for debate, though - it could take up track bed that was closed years ago, or a route that was proposed for this exact purpose in the 1930s (construction started in 1939, but stopped after the outbreak of World War 2).
Also, the South West has to cope with an ageing fleet of diesel multiple units (DMUs). For years, they have had cast-offs from other areas of the country as they get new trains. I think the last of these DMUs to be built new for service in the South West were constructed back in the 1940s or 1950s. There's the chance that trains currently in service in the Thames Valley will be used on local routes in the South West once Crossrail is in operation at the end of the decade. This would be good, as newer trains would be in service, but I would much rather have new trains constructed for the South West.
So, yeah - in short, HS2 isn't a bad idea, but I would much rather see the money be used in other areas of the country so that they can get improved rail services, most importantly (for me, at least) the South West. I know this has gone rather off-topic, but I think it's a relevant point to make with the general election looming in less than three months.