With Neihu facing a transportation crisis Taipei is looking for solutions. This situation isn't very surprising; Neihu's population has been growing faster than that of any other district in Taipei, and its single, medium-capacity MRT line was crowded upon opening and has only become more crowded since.
Several cheaper solutions have been floated, including HOV lanes, bus lanes and wider bridges (though for some reason not more cars on Neihu Line trains, which I thought was in the works already). The first two of these make sense, because they encourage more efficient use of space and energy. The most interesting suggestion however is a new MRT line linking Neihu to Xinyi. Such a line is already in Taipei's long-term plan but the alignment is bad: it makes a big semioval from Jiannan Rd. east into central Neihu then west to Minsheng Community, lengthening trip times; it crosses paths with the Songshan and Xinyi Lines but doesn't have transfers to them (not to mention to the TRA); and it doesn't actually pass through any major economic centers, forcing passengers to transfer to get where they're likely to go.
Luckily Taipei is planning an entirely new line. According to one report, this line would start at Xiangshan (hopefully as a branch of the Xinyi Line for better integration into the system), have transfers to the Bannan Line at Yongchun and the Songshan Line at Songshan, and then proceed to Neihu Science Park. This routing would both provide better connections to the rest of the MRT system and the TRA and appears to offer a more direct route. Assuming it is a branch of the Xinyi Line it would also provide direct access to at least one major economic center, the Taipei 101 area.
A route down Keelung Rd. would be even more ideal, as that could link directly to City Hall as well as 101 and Songshan, and could then be extended to Liuzhangli and Gongguan, also an important commercial area, and then into the underserved eastern section of Yonghe and Zhonghe. However, this current proposal would still be a very useful addition to Taipei's transit network.