Lisca has completed the determination of the smooth concordance orders of 2-bridge knots.
Adam Levine has shown the following knots have infinite smooth concordance order, building on the work of Grigsby, Ruberman, and Strle:
9_30,
9_33,
9_44,
10_58,
10_60,
10_102,
10_119,
10_135,
11a_4,
11a_8,
11a_11,
11a_24,
11a_26,
11a_30,
11a_52,
11a_56,
11a_67,
11a_76,
11a_80,
11a_88,
11a_126,
11a_160,
11a_167,
11a_170,
11a_189,
11a_233,
11a_249,
11a_257,
11a_265,
11a_270,
11a_272,
11a_287,
11a_288,
11a_289,
11a_300,
11a_303,
11a_315,
11a_350,
11n_12,
11n_48,
11n_53,
11n_55,
11n_110,
11n_114,
11n_130,
11n_165,
E. Grigsby, D. Ruberman, S. Strle, Knot concordance and Heegaard Floer homology invariants in branched covers, math.GT/0701460.
S. Jabuka and S. Naik, "Order in the concordance group and Heegaard Floer homology," math.GT/0611023.
A. Levine, "On knots of infinite smooth concordance order," arxiv.org/abs/0805.2410.
P. Lisca, "Sums of lens spaces bounding rational balls," arXiv:0705.1950.
C. Livingston and S. Naik, "Knot concordance and torsion," Asian J. Math. 5 (2001), no. 1, 161--167.
C. Livingston and S. Naik, "Obstructing four-torsion in the classical knot concordance group," J. Differential Geom. 51 (1999), no. 1, 1--12.
A. Tamulis, " Knots of ten or fewer crossings of algebraic order 2," J. Knot Theory Ramifications 11 (2002), no. 2, 211--222.