Since last July I have been working on a BattleCity project of my own. The client was rewritten from scratch due to instabilities in the Sourceforge project and an apparent lack of other programmers to help fix them. Once Mark left the Sourceforge project I ceased all work on it and started creating my own. Mark had taught me pretty much everything I knew about C++, such as effectively structuring a program and using linked lists correctly.
So after a long time I am able to present BattleCity, with a release date set for February 21, 2005. If you want to log on the test server (not guaranteed to be up, but it is often) you can head to http://battlecity.org/downloads/ and grab the client.