As Reading's Green Park station is being built, there has been talk of building another suburban railway station at the opposite end. There has been some talk about building a railway station in Chineham, a suburb of Basingstoke. The residential area has a population of 7,000 as well as a business park and another nearby residential estate called Popley.

This 2005 report showed things to be promising:
http://www.hants.gov.uk/decisions/decisions-docs/050406-bdhmap-R0329171640.html

On a community website, I found some information from a councillor:
http://spotlightonchineham.co.uk/forum/Blah.pl?m-1208544937/s-0/#num2

There seems to have been setbacks since, as it was suggested it could run parallel with the construction of Green Park, but it seems the Reading station succeeded at one point where the Basingstoke proposal hit a hurdle.

Yes, Reading is a bottleneck, but only for through services. In the northern corner of the station there is Platform 10 which isn't used much and another track which runs along the northern side of Platform 9. If necessary, not all trains need to terminate at Reading but it seems crazy not to extend it to Reading. Crossrail says its a connecting service, so why not extend it to Reading and connect Reading, Henley-on-Thames, Basingstoke, as well as even Birmingham (connected to Reading by CrossCountry) to Essex?.