The Nokia 5230, 5235  and 5238 got new firmware updates: v50.6.001, v50.8.001 & v50.9.002. respectively, They were in fact improved a lot , total increase in system performance, fixed several bugs and brings out the latest features.
The update is currently rolled out for U.S ans Europe versions and will out for the rest of world soon.The update is currently downloaded via OTA (Over-The-Air), or via the software NSU (Nokia Software Updater). See below for the official changelog.
 Official Changelog:

• New, faster version of the web browser, including web search integrated into the web address field, and support for multiple windows and web addresses containing non-Latin characters
• Big clock feature, displaying the time and date when you press the menu key, if the screen and keys are locked
• Emoticons can be used in text and multimedia messages
• Ovi Contacts removed
• General performance improvements

The Nokia 5230 / 5235 / 5238  has the option  of UDP (User Data Preservation), so as not remove any data during the upgrade. But you should back up your data before update to avoid any problem.