Tashkent is a very attractive and vibrant city. The roots of the rich Uzbek culture shine through Tashkent's architecture, museums and metro stations. The uzbek folk are very friendly. The best way to get a full taste of the culture would be to visit the local markets, It is a social place which every citizen in Tashkent is bound to visit. The nightlife in Tashkent is evolving at an incredible pace. There are many night clubs as well as teahouses and cafes. The uzbek food is unique and very tasty! Some of the dishes that you have to try are the plov, samsa, shaslik and a lot more. But be careful! food bought at markets may upset your stomach (for a long time, even). so either take some pill or eat some local yoghurt to build on friendly local bifido-bacteria.
Tashkent is the capital of Uzbekistan but does not have the special attractions Samarkand and Bukhara have. Most of it was destroyed by a huge earthquake in the seventies. The soviets took this disaster as an opportunity and called the working class heroes to help rebuild Tashkent. Thousants of volunteers went to the city to help and stayed afterwards, turning the ancient city into a modern, communist and rather Russian town.
The town is not unpleasant though. There may not be many sights, except for a few really good museums, but there are parks and fountains and the Stalinst like architecture is quite impressive. It is also an important hub if you wnat to go to Kyrgyzstan or Kazakhstan. There are cheap internal flights to Khiva, Bokhara and Samarkand, although the savety records of internal flights for Uzbekistan is only so so.