13. A system configured to process text input, comprising: an input device configured to receive a sequence of user inputs; and a processor coupled to the input device and configured to: assign to each of a plurality of candidate sequences of one or more characters, each associated with a candidate key which has been identified as a candidate with which a received user input is associated, an initial score based at least in part on a keyboard geometry-based value associated with the received user input with respect to the candidate key; perform further processing with respect to a subset of the candidate sequences having the highest initial score(s), without at least initially performing the same further processing with respect to one or more other candidate sequences not in the subset, to determine for each candidate sequence in the subset a refined score; and select a candidate sequence for inclusion in a result set based at least in part on a determination that a refined score of the selected candidate is higher than an initial score of one or more candidate sequences that are not included in the subset and with respect to which the further processing has not been performed.
13. A system configured to process text input, comprising: an input device configured to receive a sequence of user inputs; and a processor coupled to the input device and configured to: assign to each of a plurality of candidate sequences of one or more characters, each associated with a candidate key which has been identified as a candidate with which a received user input is associated, an initial score based at least in part on a keyboard geometry-based value associated with the received user input with respect to the candidate key; perform further processing with respect to a subset of the candidate sequences having the highest initial score(s), without at least initially performing the same further processing with respect to one or more other candidate sequences not in the subset, to determine for each candidate sequence in the subset a refined score; and select a candidate sequence for inclusion in a result set based at least in part on a determination that a refined score of the selected candidate is higher than an initial score of one or more candidate sequences that are not included in the subset and with respect to which the further processing has not been performed. 18. The system of claim 13 , wherein the further processing includes using a language model to determine the refined score; and wherein the system further includes a storage device configured to store the language model.