The second handset is the C5510, which looks very nice as well, but has a smaller 2.2-inch TFT display and the same resolution. According to the source, what you will get purchasing this one will probably be 2-megapixel camera, microSDHC slot and 512 MB of storage. It seems the C5510 will be a quad-band GSM phone, but will lack 3G support.
Current expectations point at a summer release for both phones, but their future pricing is still unknown.
source: mobil.cz (translated)
The Samsung C5510 and S6700 are stylish sliders